Expressas a rational number with denominator
(i) 20 (ii) -30 (iii) 35 (iv) -40
For a fraction,
Where, n ≠ 0
(i) We have to express as a rational number with denominator 20.
In order to make the denominator 20, multiply 5 by 4.
Therefore,
(ii) We have to express as a rational number with denominator -30.
In order to make the denominator -30, multiply 5 by -6.
Therefore,
(iii) We have to express as a rational number with denominator 35.
In order to make the denominator 35, multiply 5 by 7.
Therefore,
(iv) We have to express as a rational number with denominator -40.
In order to make the denominator 20, multiply 5 by -8.
Therefore,
Expressas a rational number with denominator 7.
For a fraction,
Where, n ≠ 0 and n divides both a and b
(i) We have to express as a rational number with denominator 7.
In order to make the denominator 7, divide 98 by 14.
Therefore,
Expressas a rational number with denominator 5.
For a fraction,
Where, n ≠ 0 and n divides both a and b
We have to express as a rational number with denominator 5.
In order to make the denominator 5, divide 60 by 12.
Therefore,
Express each of the following rational numbers in standard form:
(i) (ii) (iii) (iv)
A rational number is in standard or simplest or lowest form when-
1. Numerator and denominator have only 1 as its highest common factor.
2. Denominator is a positive integer.
(i) The HCF of 12 and 30 is 6
Therefore,
(ii) The HCF of 49 and 14 is 7
Therefore,
(iii) The HCF of 24 and 64 is 8
Therefore,
In order, to make the denominator positive, multiply both numerator and denominator by -1
(iv) The HCF of 36 and 63 is 9
Therefore,
In order, to make the denominator positive, multiply both numerator and denominator by -1
Which of the two rational numbers is greater in the given pair?
(i) or 0 (ii)or 0 (iii)or
(iv)or (v)or (vi)or
(i) is a positive number and all positive numbers are greater than 0.
Therefore,
(ii) is a negative number and all negative numbers are less than 0.
Therefore,
(iii) Both and have the same denominator 4.
Therefore, we can directly compare both the numbers.
Since, 1 > -3
Therefore,
(iv) Both and have the same denominator 7.
Therefore, we can directly compare both the numbers.
Since, -4 > -5
Therefore,
(v) and have different denominators.
Therefore, we take LCM of 3 and 4 that is 12.
Now,
And,
Since, 9 > 8
Therefore,
Hence,
(vi) We can write
and have different denominators.
Therefore, we take LCM of 1 and 2 that is 2.
Now,
And,
Since, -1 > -2
Therefore,
Hence,
Which of the two rational numbers is greater in the given pair?
(i)or (ii)or (iii)or
(iv)or(v)or (vi)or
(i) and have different denominators.
Therefore, we take LCM of 3 and 7 that is 21.
Now,
And,
Since, -24 > -28
Therefore,
Hence,
(ii)
and have different denominators.
Therefore, we take LCM of 9 and 8 that is 72.
Now,
And,
Since, -45 > -56
Therefore,
Hence,
(iii)
and have different denominators.
Therefore, we take LCM of 3 and 5 that is 15.
Now,
And,
Since, -5 > -12
Therefore,
Hence,
(iv)
And,
and have different denominators.
Therefore, we take LCM of 13 and 12 that is 156.
Now,
And,
Since, -91 > -108
Therefore,
Hence,
(v)
and have different denominators.
Therefore, we take LCM of 10 and 5 that is 10.
Now,
And,
Since, -7 > -8
Therefore,
Hence,
(vi)
We can write
and have different denominators.
Therefore, we take LCM of 1 and 5 that is 5.
Now,
And,
Since, -12 > -15
Therefore,
Hence,
Fill in the blanks with the correct symbol out of >, = and <:
(i) (ii)(iii)
(iv) (v) (vi)
(i) Clearly,
(ii)
and have different denominators.
Therefore, we take LCM of 13 and 91 that is 91.
Now,
And,
Clearly,
Hence,
(iii) We can write
and have different denominators.
Therefore, we take LCM of 1 and 5 that is 5.
Now,
And,
Since, -10 > -13
Therefore,
Hence,
(iv)
and have different denominators.
Therefore, we take LCM of 3 and 8 that is 24.
Now,
And,
Since, -16 < -15
Therefore,
Hence,
(v)
is a positive number and all positive numbers are greater than 0.
Therefore,
Hence,
(vi) and have different denominators.
Therefore, we take LCM of 9 and 10 that is 90.
Now,
And,
Since, -80 > -81
Therefore,
Hence,
Arrange the following rational numbers in ascending order:
(i) (ii)
(iii) (iv)
(i)
And,
Since, the denominators of all the numbers are different therefore we will take LCM of the denominators.
LCM of 9, 12, 18 and 3 = 36
Clearly,
-24 < -16 < -15 < -14
Therefore,
Hence,
(ii)
And,
Since, the denominators of all the numbers are different therefore we will take LCM of the denominators.
LCM of 4, 12, 16 and 24 = 48
Clearly,
-36 < -21 < -20 < -18
Therefore,
Hence,
(iii)
Since, the denominators of all the numbers are different therefore we will take LCM of the denominators.
LCM of 5, 10, 15 and 20 = 60
Clearly,
-44 < -42 < -39 < -36
Therefore,
Hence,
(iv)
Since, the denominators of all the numbers are different therefore we will take LCM of the denominators.
LCM of 7, 14, 28 and 42 = 84
Clearly,
-54 < -48 < -46 < -39
Therefore,
Hence,
Arrange the following rational numbers in descending order:
(i) (ii)
(iii) (iv)
(i)
And,
Since, the denominators of all the numbers are different therefore we will take LCM of the denominators.
LCM of 1, 6and 3 = 6
Clearly,
2 > -12 > -13 > -16
Therefore,
Hence,
(ii)
And,
Since, the denominators of all the numbers are different therefore we will take LCM of the denominators.
LCM of 10, 15, 20 and 30 = 60
Clearly,
-18>-28>-33>-34
Therefore,
Hence,
(iii)
Since, the denominators of all the numbers are different therefore we will take LCM of the denominators.
LCM of 6, 12, 18 and 24 = 72
Clearly,
-42>-52>-60>-69
Therefore,
Hence,
(iv)
Since, the denominators of all the numbers are different therefore we will take LCM of the denominators.
LCM of 11, 22, 33 and 44 = 132
Clearly,
-92>-114>-117>-120
Therefore,
Hence,
Which of the following statements are true and which are false?
(i) Every whole number is a rational number.
(ii) Every integer is a rational number.
(iii) 0 is a whole number but it is not a rational number.
(i) Every whole number a can be represented as
Therefore, every whole number is a rational number.
(ii) Every integer a can be represented as
Therefore, every integer is a rational number.
(iii) 0 can be represented as
Therefore, 0 is a whole number and a rational number.
Represent each of the following numbers on the number line:
(i) (ii) (iii)(iv)
(v) (vi) (vii)(viii)
(i) is greater than 0 and less than 1.
Therefore, it lies between 0 and 1
(ii) is greater than 0 and less than 1.
Therefore, it lies between 0 and 1
(iii)
is greater than 1 and less than 2.
Therefore, it lies between 1 and 2
(iv)
is greater than 2 and less than 3.
Therefore, it lies between 2 and 3.
(v)
is greater than 3 and less than 4.
Therefore, it lies between 3 and 4.
(vi)
is greater than 5 and less than 6.
Therefore, it lies between 5 and 6.
(vii)
is greater than 4 and less than 5.
Therefore, it lies between 4 and 5.
(viii) The number line representation of 8 is
Represent each of the following numbers on the number line:
(i) (ii) (iii) (iv)
(v) (vi) (vii) (viii)
(i) is greater than -1 and less than 0.
Therefore, it lies between -1 and 0
(ii) is greater than -1 and less than 0.
Therefore, it lies between -1 and 0
(iii)
is greater than -2 and less than -1`.
Therefore, it lies between -2 and -1
(iv)
is greater than -8 and less than -7`.
Therefore, it lies between -8 and -7
(v)
is greater than -5 and less than -4.
Therefore, it lies between -5 and -4
(vi)
is greater than -3 and less than -2.
Therefore, it lies between -3 and -2
(vii) The number line representation of -3 is
(viii)
is greater than -3 and less than -2.
Therefore, it lies between -3 and -2
Which of the following statements are true and which are false?
(i) lies to the left of 0 on the number line.
(ii)lies to the right of 0 on the number line.
(iii) The rational numbersandare on opposite sides of 0 on the number line.
(iv) The rational numberlies to the left of 0 on the number line.
(i) True
is a negative number.
All negative numbers are less than 0 and therefore, lie to the left of 0 on the number line.
Hence, lies to the left of 0 on the number line.
(iii) False
is a negative number.
All negative numbers are less than 0 and therefore, lie to the left of 0 on the number line.
Hence, lies to the left of 0 on the number line.
(iii)True
is a positive number.
All positive numbers are greater than 0 and therefore, lie to the right of 0 on the number line.
Hence, lies to the right of 0 on the number line.
is a negative number.
All negative numbers are less than 0 and therefore, lie to the left of 0 on the number line.
Hence, lies to the left of 0 on the number line.
Therefore, the rational numbers, and are on opposite sides of 0 on the number line.
(iv) False
is a positive number.
All positive numbers are greater than 0 and therefore, lie to the right of 0 on the number line.
Hence, lies to the right of 0 on the number line.
Add the following rational numbers:
(i)and (ii)and (iii)and
(iv)and (v)and (vi)and
(i)
(ii)
(iii)
To convert it into lowest terms, divide both numerator and denominator by common divisor of both 6 and 8 that is, 2
(iv)
To convert it into lowest terms, divide both numerator and denominator by common divisor of both 6 and 3 that is, 3.
=2
(v)
To convert it into lowest terms, divide both numerator and denominator by common divisor of both 4 and 6 that is, 2.
(vi)
To convert it into lowest terms, divide both numerator and denominator by common divisor of both 18 and 15 that is, 3.
Add the following rational numbers:
(i) and (ii) and (iii)and
(iv)and (v)and
(vi)and (vii)and
(viii)and (ix)and
(i) Since, the denominators of given rational numbers are different therefore, we take their LCM.
LCM of 4 and 5 = 20
And
Now,
(ii) Since, the denominators of given rational numbers are different therefore, we take their LCM.
LCM of 8 and 12 = 24
And
Now,
(iii) Since, the denominators of given rational numbers are different therefore, we take their LCM.
LCM of 9 and 6 = 18
And
Now,
(iv) Since, the denominators of given rational numbers are different therefore, we take their LCM.
LCM of 16 and 24 = 48
And
Now,
(v) Since, the denominators of given rational numbers are negative therefore, we will make them positive.
Now, since, the denominators of given rational numbers are different therefore, we take their LCM.
LCM of 18 and 27 = 54
And
Now,
(vi) Since, the denominators of given rational numbers are negative therefore, we will make them positive.
And,
Now, since, the denominators of given rational numbers are different therefore, we take their LCM.
LCM of 12 and 15 = 60
And
Now,
(vii) We can write -1 as .
Now, since, the denominators of given rational numbers are different therefore, we take their LCM.
LCM of 1 and 4 = 4
And
Now,
(viii) We can write 2 as .
Now, since, the denominators of given rational numbers are different therefore, we take their LCM.
LCM of 1 and 4 = 4
And
Now,
(ix)
On adding, any number to 0 we get the same number.
Therefore,
Verify the following:
(i) (ii)
(iii)(iv)
(i)LCM of 5 and 7 = 35
And,
Similarly,
LCM of 7 and 5 = 35
And,
i.e., LHS = RHS
Hence,
Verified
(ii)LCM of 13 and 8 = 104
And,
Similarly,
LCM of 8 and 13 = 104
And,
i.e., LHS = RHS
Hence,
Verified
(iii) 3 can be written as
LCM of 1 and 12 = 12
And,
Similarly,
LCM of 1 and 12 = 12
And,
i.e., LHS = RHS
Hence,
Verified
(iv) Since, the denominators are negative we will make them positive.
And,
LCM of 7 and 35 = 35
And,
Similarly,
LCM of 7 and 5 = 35
And,
i.e., LHS = RHS
Hence,
Verified
Verify the following:
(i)
(ii)
(iii)
(i)
RHS = LHS
Verified
(ii)
RHS = LHS
Verified
(iii)
RHS = LHS
Verified
Fill in the blanks:
(i)
(ii)
(iii)
(iv)
(v)
(vi)
(i)
By Commutative property, i.e., a+b=b+a
Therefore,
(ii)
By Commutative property, i.e., a+b=b+a
Therefore,
(iii)
By Associative property, i.e., (a+b)+c=a+(b+c)
Therefore,
(iv)
By Associative property, i.e., (a+b)+c=a+(b+c)
Therefore,
(v)
By Associative property, i.e., (a+b)+c=a+(b+c)
Therefore,
(vi) 0,0
0 is the additive identity that is, if we add 0 to any number the result will be the number itself.
a+0=0+a
Also, By Commutative property, i.e., a+b=b+a
We get,
Find the additive inverse of each of the following:
(i) (ii) (iii) (iv) (v)
(vi) (vii) (viii) (ix) (x)
Additive inverse of a number is the number such that,
Therefore,
(i) Additive inverse of is
(ii) Additive inverse of is
(iii) Additive inverse of -18 is 18
(iv) Additive inverse of is
(v)
Therefore, Additive inverse of is
(vi)
Additive inverse of is
(vii) Additive inverse of is
(viii) Additive inverse of is
(ix)
Therefore, Additive inverse of is
(x)
Additive inverse of is
Subtract:
(i)from (ii)from
(iii)from (iv)from
(v)from (vi)from
(vii)from (viii)from
(i)
Since the denominators of both the numbers are different therefore, we will take their LCM
LCM 0f 3 and 4 = 12
And,
Therefore,
(ii)
Since the denominators of both the numbers are different therefore, we will take their LCM
LCM 0f 6 and 3 = 6
And,
Therefore,
(iii)
Since the denominators of both the numbers are different therefore, we will take their LCM
LCM 0f 9 and 5 = 45
And,
Therefore,
(iv)
We can write,
Since the denominators of both the numbers are different therefore, we will take their LCM
LCM 0f 1 and 7 =7
And,
Therefore,
(v)
We can write,
Since the denominators of both the numbers are different therefore, we will take their LCM
LCM 0f 1 and 11 = 11
And,
Therefore,
(vi)
(vii)
Since the denominators of both the numbers are different therefore, we will take their LCM
LCM 0f 13 and 5 = 65
And,
Therefore,
(viii)
We can write,
Since the denominators of both the numbers are different therefore, we will take their LCM
LCM 0f 1 and 7 = 7
And,
Therefore,
Using the rearrangement property find the sum:
(i)
(ii)
(iii)
(iv)
Rearrangement property says that, the numbers in an addition expression may be arranged and grouped in any order.
Therefore,
(i)
We arrange the numbers with same denominators together,
Now, we take LCM of 3 and 5=15
And,
Therefore,
(ii)
We arrange the numbers,
LCM of 3 and 6 =6
And,
LCM of 4 and 8 =8
And,
Now,
Now, we take LCM of 6 and 8=24
And,
Therefore,
In lowest terms,
(iii)
We arrange the numbers,
LCM of 20 and 10 =20
And,
LCM of 14 and 7 =14
And,
Now,
Now, we take LCM of 20 and 14=140
And,
Therefore,
(iv)
We arrange the numbers,
LCM of 4 and 9 =18
And,
Now,
In lowest terms,
Now, we take LCM of 1 and 18=18
And,
Therefore,
The sum of two rational numbers is. If one the numbers isfind the other.
Sum of two rational numbers = -2
One number =
Let the other rational number = x
Now,
According to question,
Therefore, the other rational number is
The sum of two rational numbers isIf one of the numbers isfind the other.
Sum of two rational numbers =
One number =
Let the other rational number = x
Now,
According to question,
In lowest terms,
Therefore, the other rational number is
What number should be added toso as to get?
Let the number = x
Now,
According to question,
Therefore, should be added to so as to get
What number should be added toso as to get?
Let the number = x
Now,
According to question,
Therefore, should be added to so as to get
What number should be subtracted fromto get?
Let the number = x
Now,
According to question,
In lowest terms,
Therefore, should be subtracted from so as to get
(i) Which rational number is its own additive inverse?
(ii) Is the difference of two rational numbers a rational number?
(iii) Is addition commutative on rational numbers?
(iv) Is addition associative on rational numbers?
(v) Is subtraction commutative on rational numbers?
(vi) Is subtraction associative on rational numbers?
(vii) What is the negative of a negative rational number?
(i) A Additive inverse of a number is the number such that,
0 is the rational number that is its own additive inverse
(ii) Let there be 2 rational numbers, and where, b≠0 and d≠0
LCM of b and d = bd
Where, bd ≠ 0
Therefore, is a rational number
Hence,
Yes, the difference of two rational numbers a rational number
(iii) Yes, addition is commutative on rational numbers
Let there be 2 rational numbers, and where, b≠0 and d≠0
Then,
(iv) Yes, addition is associative on rational numbers
Let there be 3 rational numbers, , and where, b≠0 , d≠0 and f≠0
Then,
(v) No, subtraction is not commutative on rational numbers
Let there be 2 rational numbers, and where, b≠0 and d≠0
Then,
(vi) No, addition is not associative on rational numbers
Let there be 3 rational numbers, , and where, b≠0 , d≠0 and f≠0
Then,
(vii) Negative of a negative rational number is the number itself without the negative sign.
Find each of the following products:
(i) (ii) (iii)
(iv) (v) (vi)
(vii) (viii) (ix)
(x) (xi)
(xii)
(i)
(ii)
(iii)
In lowest terms,
(iv)
In lowest terms,
(v)
In lowest terms,
Further,
(vi)
In lowest terms,
(vii)
In lowest terms,
(viii)
In lowest terms,
Further,
(ix)
In lowest terms,
(x)
In lowest terms,
Further,
(xi)
In lowest terms,
Further,
(xii)
In lowest terms,
Verify each of the following:
(i) (ii)
(iii)
(iv)
(i)
In lowest terms,
In lowest terms,
LHS=RHS
Verified
(ii)
LHS=RHS
Verified
(iii)
In lowest terms,
In lowest terms,
LHS=RHS
Verified
(iv)
In lowest terms,
In lowest terms,
LHS=RHS
Verified
Verify each of the following:
(i)
(ii) �
(iii)
(i)
In lowest terms,
In lowest terms,
LHS=RHS
Verified
(ii)
In lowest terms,
Further,
In lowest terms,
Further,
LHS=RHS
Verified
(iii)
In lowest terms,
Further,
In lowest terms,
Further,
LHS=RHS
Verified
Fill in the blanks:
(i)
(ii)
(iii)
(iv)
(i)
By Commutative Property, i.e, a × b = b × a
(ii)
By Commutative Property, i.e, a × b = b × a
(iii)
By Associative Property, i.e, (a × b) × c = a × (b × c)
(iv)
By Associative Property, i.e, (a × b) × c = a × (b × c)
Find the multiplicative inverse (i.e., reciprocal) of:
(i) (ii) (iii) (iv) (v)
(vi) (vii) (viii) (ix) (x)
A multiplicative inverse for a number x, is a number which when multiplied by x yields the multiplicative identity, 1
The multiplicative inverse of a rational number is.
Therefore,
(i) The multiplicative inverse of =.
(ii) The multiplicative inverse of =.
In standard form,
(iii) The multiplicative inverse of =.
In standard form,
.
(iv) The multiplicative inverse of =.
(v) The multiplicative inverse of =.
(vi) The multiplicative inverse of =.
In standard form,
(vii) The multiplicative inverse of -1 =-1.
(viii) The multiplicative inverse of is undefined.
Since, is undefined.
(ix) The multiplicative inverse of =.
(x) The multiplicative inverse of =.
In standard form,
Find the value of:
(i)(ii) (iii) (iv)
Let there be a rational number then =
Therefore,
(i)
(ii)
(iii)
(iv)
Verify the following:
(i)
(ii)
(iii)
(iv)
(i)
In lowest terms,
In lowest terms,
LHS=RHS
Verified
(ii)
In lowest terms,
In lowest terms,
LHS=RHS
Verified
(iii)
In lowest terms,
In lowest terms,
LHS=RHS
Verified
(iv)
In lowest terms,
In lowest terms,
LHS=RHS
Verified
Name the property of multiplication illustrated by each of the following statements:
(i)
(ii)
(iii)
(iv)
(v)
(vi)
(i) Commutative law i.e., a b = b a
(ii) Associative law i.e., a(bc) = (ab)c
(iii) Distributive law i.e., a(b + c) = ab + ac
(iv) Property of multiplicative identity i.e., a× 1=1× a
(v) Property of multiplicative inverse i.e., =1
(vi) Multiplicative property of 0 i.e., a× 0=0
Fill in the blanks:
(i) The product of a rational number and its reciprocal is........
(ii) Zero has……reciprocal.
(iii) The numbers…… and….are their own reciprocals.
(iv) Zero is……the reciprocal of any number.
(v) The reciprocal ofwhereis……
(vi) The reciprocal ofwhereis……
(vii) The reciprocal of a positive rational number is……
(viii) The reciprocal of a negative rational number is……
(i) 1
(ii) No
(iii) 1 and -1
(iv) Not
(v)
(vi) a
(vii) Positive
(viii) Negative
Simplify:
(i)(ii) (iii)(iv) (v) (vi)
(i)
In lowest terms,
(ii)
(iii)
In lowest terms,
(iv)
In lowest terms,
(v)
In lowest terms,
(vi)
In lowest terms,
Further,
Verify whether the given statement is true or false:
(i)
(ii)
(iii)
(iv)
(i)
Since, RHS = LHS
Therefore, True
(ii)
Since, RHS ≠ LHS
Therefore, False
(iii)
Since, RHS ≠ LHS
Therefore, False
(iv)
Since, RHS ≠ LHS
Therefore, False
Verify whether the given statement is true or false:
(i)
(ii)
(iii)
(i)
RHS ≠ LHS
Hence, False
(ii)
RHS ≠ LHS
Hence, False
(iii)
RHS ≠ LHS
Hence, False
The product of two rational numbers is -9. If one of the numbers is -12, find the other.
Product of two rational numbers = -9
One rational number = -12
Let the other rational number = x
Now,
According to the question,
-12 × x = -9
Hence, the other rational number is
The product of two rational numbers is .If one of the numbers is find the other.
Product of two rational numbers =
One rational number =
Let the other rational number = x
Now,
According to the question,
Hence, the other rational number is
By what rational number should we multiply to get ?
Let x be multiplied by to get
It can be written as,
Hence, it should be multiplied by is
By what rational number should be multiplied to obtain ?
Let x be multiplied by to get
It can be written as,
Hence, it should be multiplied by is
By what number should be divided to get ?
Let be divided by x to get
It can be written as,
Hence, it should be multiplied by is
Divide the sum of and by the product of and
Sum of and -
Product of and -
Now,
According to the question,
Divide the sum of and by their differ-renice.
According to the question,
Fill in the blanks:
(i) (ii)
(iii) (iv)
(i)
Therefore,
(ii)
Therefore,
(iii)
Therefore,
(iv)
Therefore,
(i) Are rational numbers always closed under division?
(ii) Are rational numbers always commutative under division?
(iii) Are rational numbers always associative under division?
(iv) Can we divide 1 by 0?
(i) No rational numbers are not always closed under division,
Since, which is not a rational number
(ii) No rational numbers are not always commutative under division,
Let and be two rational numbers.
And
Therefore,
Hence, rational numbers are not always commutative under division
(iii) No rational numbers are not always associative under division,
Let , and be two rational numbers.
And
Therefore,
Hence, rational numbers are not always associative under division.
(iv) No we cannot divide 1 by 0.
Since, which is not defined.
Find a rational number betweenand
To find a rational number x between two rational numbers and , we use
Therefore, to find rational number x (let) between and
Find a rational number betweenand.
To find a rational number x between two rational numbers and , we use
Therefore, to find rational number x (let) between 2 and 3
Find a rational number betweenand
To find a rational number x between two rational numbers and , we use
Therefore, to find rational number x (let) between and
Find two rational numbers betweenand.
To find a rational number x between two rational numbers and , we use
Therefore, to find rational number x (let) between -3 and -2
Now if we find a rational number between and -2 it will also be between -3 and -2 since lies between -3 and -2
Therefore, to find rational number y (let) between and -2
Find three rational numbers betweenand
To find a rational number x between two rational numbers and , we use
Therefore, to find rational number x (let) between 4 and 5
Now if we find a rational number between and it will also be between 4 and 5 since lies between 4 and 5
Therefore, to find rational number y (let) between and
Now if we find a rational number between and 5it will also be between 4 and 5 since lies between 4 and 5
Therefore, to find rational number z (let) between and 5
Find three rational numbers betweenand
To find a rational number x between two rational numbers and , we use
Therefore, to find rational number x (let) between and
Now if we find a rational number between and it will also be between and since lies between and
Therefore, to find rational number y (let) between and
Now if we find a rational number between andit will also be between and since lies between and
Therefore, to find rational number z (let) betweenand
Find 10 rational numbers betweenand
We can write as (Since,
And,
We can write as (Since,
Now clearly, rational numbers between them are,
Any 10 rational numbers are,
Find 12 rational numbers between -1and 2.
We can write as (Since,
And,
We can write 2 as (Since,
Now clearly any 12 rational numbers between -1 and 2 are,
From a rope 11 m long. two pieces of lengthsm andm are cut off. What is the length of remaining rope?
Length of rope = 11 m
Length of first piece cut = 2
Length of second piece cut = 3
Total length cut = Length of first piece cut + Length of second piece cut
Length of remaining rope = Length of rope - Total length cut
Hence, Length of remaining rope =
A drum full of rice weight kg. If the empty drum weight kg. Find the weight of rice in the drum.
Weight of drum full of rice = kg
Weight of empty drum = kg
Weight of rice Weight of drum full of rice - Weight of empty drum
Hence, Weight of rice =
A basket contains three types of fruits weightkg in all. Ifkg of these be apples,kg be oranges and the rest pears, what is the weight of the pears in the basket?
Weight of basket with three types of fruits = kg
Weight of apples = kg
Weight of oranges = kg
Weight of pears = Weight of basket with three types of fruits – (Weight of apples + Weight of oranges )
Hence, Weight of pears
On one day a rickshaw puller earned Rs. 160. Out of his earnings he spenton tea and snacks, Rs.on food and Rs.on repairs of the rickshaw. How much did he save on that day?
Total Earnings = Rs 160
Spend on tea and snacks = Rs
Spend on food = Rs
Spend on repairs = Rs
Total Expenditure = Spend on tea and snacks + Spend on food + Spend on repairs
Savings= Total Earnings - Total Expenditure
Hence, Savings =
Find the cost ofmeters of cloth at Rs.per meter.
Cost of cloth per meter =
Total meters =
Cost of total cloth = Cost of cloth per meter × Total meters
Therefore, total cost
A car is moving at an average speed ofkm/hr. How much distance will it cover inhours?
Speed of car =
Total hours =
Total Distance = Speed of car × Total hours
Therefore, Total Distance
Find the area of a rectangular park which ism long andm board.
Length of park =
Breadth of park =
Area of park = Length of park × Breadth of park
Hence, Area of park
Find the area of square plot of land whose each side measuremeters.
Side of plot =
Area of plot = Side of plot × Side of plot
Hence, Area of plot
One liters of petrol costs Rs.What is the cost of 34 liters of petrol?
Cost of one litre petrol =
Cost of 34 litre petrol = 34 × Cost of one litre petrol
Cost of 34 litre petrol
An aeroplane covers 1020 km in an hour. How much distance will it cover inhours?
Distance covered in one hour = 1020 km
Distance covered in hours = × Distance covered in one hour
Distance covered in hours
The cost ofmeters of cloth is Rs.. What is the cost of one metre of cloth?
Cost of of cloth = Rs
Cost of of cloth = Cost of of cloth
Cost of of cloth
A cord of lengthm has been cut into 26 pieces of equal length. What is the length of each piece?
Length of cord = 71
No of pieces = 26
Length of each piece = Length of cord No of pieces
Length of each piece
The area of a room is. If its breadth ismeters, what is its length?
Area of room =
Breadth of room =
Length of room = Area of room Breadth of room
Length of room
The product of two fractions isIf one of the fractions isfind the other.
Product of two fractions = 9
First fraction = 9
Second fraction = Product of two fractions ÷ First fraction
Second fraction
In a schoolof the students are boys. If there are 240 girls, find the number of boys in the school.
Fraction of boys =
Fraction of girls =1- =
Number of girls= 240
Number of girls = Total students ×
⇒ 240 = Total students ×
⇒ Total students = 240 ÷
Total students =640
Number of boys = Total students - Number of girls
=640 – 240 = 400
Number of boys= 400
After readingof a book, 40 pages are left. How many pages are there in the book?
Fraction read =
Fraction left =
Pages left = 40
Pages left = Total pages
40= Total pages
⇒ Total pages =
Total pages = 180
Rita had Rs. 300. She spentof her money on notebooks andof the remainder on stationary items. How much money is left with her?
Total money = Rs 300
Fraction spent on notebooks =
Amount spent on notebooks = = Rs 100
Amount left = Rs 300 – Rs 100 =Rs 200
Fraction spent on stationary =
Amount spent on stationary = = Rs 50
Money left = Rs 300 – Rs 150 = Rs 150
Amit earns Rs. 32000 per month. He spendsof his income on food;of the remainder on house rent andof the remainder on the education of children. How much money is still left with him?
Total earnings = Rs 32000
Amount spend on food =
Amount left = Rs 32000 - Rs 8000 = Rs 24000
Amount spend on house rent =
Amount left = Rs 24000- Rs 7200 = Rs 16800
Amount spend on education =
Amount left = Rs 16800 - = Rs 12800
Money left = Rs 12800
Ifof a number exceeds itsby, find the number.
Let the number be x
of x =
of x =
According to the question,
The number is 140
At a cricket test matchof the spectators were in a covered place while 15000 were in open. Find the total number of spectators.
Fraction of spectators covered =
Fraction left =
Number of spectators in open = 15000
According to the question,
Number of spectators in open = Total number of spectators ×
Options A.
B.
C.
D.
LCM of 12 and 16 = 48
Options A.
B.
C.
D.
And,
Options A.
B.
C.
D.
Options A.
B.
C.
D.
Options A.
B.
C.
D.
What should be added toto get
Options A.
B.
C.
D.
Let the number added be x.
Then,
Options A.
B.
C.
D.
LCM of 3, 5, 15, 20
The sum of two numbers isto get
Options A.
B.
C.
D.
Let the number added be x.
Then,
What should be added toto get
Options A.
B.
C.
D.
Let the number added be x.
Then,
What should be subtracted fromto get
Options A.
B.
C.
D.
Let the number subtracted be x.
Then,
Options A.
B.
C.
D. none of these
We know,
For any real number a≠0,
So,
The product of two rational numbers is. If one of the numbers isthen the other one is
Options A.
B.
C.
D.
Let the other number be x.
Then,
The product of two numbers is. If one of the numbers isthe other is
Options A.
B.
C.
D.
Let the other number be x.
Then,
What should be subtracted fromto get
Options A.
B.
C.
D.
Let the number subtracted be x.
Then,
The sum of two rational numbers isIf one of them isthen the other one is
Options A.
B.
C.
D.
Let the other number be x.
Then,
Which of the following numbers is in standard form?
Options A.
B.
C.
D.
is not in standard form since 12 and 26 have a common divisor 2.
is not in standard form since its denominator is negative.
Therefore, only and are in standard forms as their numerator and denominator have no common divisor and their denominators are positive.
Options A.
B.
C.
D.
Options A.
B.
C.
D.
Options A.
B.
C.
D.
Additive inverse ofis
Options A.
B.
C.
D.
Additive inverse of a number is the number such that,
Therefore,
Additive inverse of is
Reciprocal ofis
Options A.
B.
C.
D. 0
Reciprocal of
A rational number betweenandis
Options A.
B.
C.
D.
Rational number between and
The reciprocal of a negative rational number
Options A. is a positive rational number
B. is a negative rational number
C. can be either a positive or a negative rational number
D. does not exist
Let be a negative rational number
Then, its reciprocal will be which is also a negative rational number.
Hence, the reciprocal of a negative rational number is a negative rational number
Find the additive inverse of(i)(ii)
Additive inverse of a number is the number such that,
Therefore,
(i)
Additive inverse of is
(ii) Additive inverse of is
The sum of two rational numbers isIf one of them isfind the other.
Sum of two rational numbers = -4
First number =
Second number = Sum of two rational numbers - First number
Second number
What number should be added toto get
Let the number added be x
Then,
What number should be subtracted fromto get
Let the number subtracted be x
Then,
Find the multiplicative inverse of (i)(ii)
Multiplicative inverse of a rational number
Therefore,
(i) Negative inverse of
(ii) Negative inverse of
The product of two numbers is. If one of them is, find the other.
Let the other number be x
Then,
Evaluate:
(i) (ii) (iii)
(i)
(ii)
(iii)
Name the property of multiplication shown by each of the following statements:
(i) (ii)
(iii)
(iv)
(v)
(i) Commutative law of multiplication i.e., a b = b a
(ii) 1 as multiplicative identity i.e., a × 1 = b × 1
(iii) Associative law of multiplication i.e., a(bc) = (ab)c
(iv) Multiplicative property of 0 i.e., a× 0=0
(v) Distributive law of multiplication over addition i.e., a(b + c) = ab + ac
Find two rational numbers lying betweenand
Rational number between and
Now,
Rational number between and
What should be added toto get ?
Options A.
B.
C.
D.
Let the number added be x
Then,
What should be added toto get
Options A.
B.
C.
D.
Let the number added be x
Then,
Options A.
B.
C.
D.
The product of two numbers isIf one of them isthen the other is
Options A.
B.
C.
D.
Let the other number be x
Then,
Options A.
B.
C.
D.
Options A.
B.
C.
D.
Reciprocal ofis
Options A.
B.
C.
D. none of these
Reciprocal of
A rational number betweenandis
Options A.
B.
C.
D.
Rational number between and
Fill in the blanks.
(i)
(ii)
(iii)
(iv)
(i)
(ii)
(iii)
(iv)
Write ‘T’ for true and ‘F’ for false for each of the following:
(i) Rational numbers are always closed under subtraction.
(ii) Rational numbers are always closed under division.
(iii)
(iv) Subtraction is commutative on rational numbers.
(v)
(i) true
Let there be two rational numbers and
Then,
which is also a rational number
Hence, Rational numbers are always closed under subtraction.
(ii) false
Hence, Rational numbers are not always closed under division.
(iii) false
Hence,
(iv) false
Let there be two rational numbers and
Then,
And
Therefore,
Hence, Subtraction is not commutative on rational numbers.
(v) true