Chapter 6: Fractions – Exercise 6.9

Question: 1

Add:

i) 3/4 and 5/6

ii) 7/10 and 2/15

iii) 8/13 and 2/3

iv) 4/5  and  7/15

Solution:

i) Given: 3/4 and 5/6

LCM of 4 and 6 is 12, so we will convert each fraction into an equivalent fraction with denominator 12.

ii) Given: 7/10 and 2/15

LCM of 10 and 15 is 30, so we will convert each fraction into an equivalent fraction with denominator 30.

iii) Given: 8/13 and 2/3

LCM of 13 and 3 is 39, so we will convert each fraction into an equivalent fraction with denominator 39.

iv) Given: 4/5 and 7/15

LCM of 5 and 15 is 1, so we will convert each fraction into an equivalent fraction with denominator 15.

Question: 2

Subtract:

Solution:

i) Given: 2/7 and  19/21

LCM of 21 and 7 is 21, so we will convert each fraction into an equivalent fraction with denominator 21.

ii) Given: 21/25 and 18/20

LCM of 20 and 25 is 100, so we will convert each fraction into an equivalent fraction with denominator 100.

iii) Given: 2/1 and 7/16

LCM of 1 and 16 is 16, so we will convert each fraction into an equivalent fraction with denominator 16.

LCM of 5 and 15 is 15, so we will convert each fraction into an equivalent fraction with denominator 15.

Question: 3

Find the difference of:

i) 13/24 and 7/16

i)  5/18 and 4/15

i)  1/12 and 3/4

i) 2/3 and 6/7

Solution:

i) Given: 13/24 and 7/16

ii) Given: 5/18 and 4/15

iii) Given: 3/4 and 1/12

iv) Given: 6/7 and 2/3

Question: 4

Subtract as indicated:

Solution:

i) Given: 8/3 and 5/9

Question: 5

Simplify:

Solution:

Question: 6

Replace * with a correct number:

Solution:

Therefore, 7/8

Question: 7

Savita bought 2/5 m of ribbon and kavita 3/4 m of ribbon. What was the total length of the ribbon they bought?

Solution:

Length of the ribbon bought by savita = 2/5 metres

Length of the ribbon bought by kavita = 3/4 metres

Total length of the ribbon bought by them:

Question: 8

Ravish takesminutes to walk across the school ground. Rahul takes 7/4 minutes to do the same. Who takes less time and by what fraction?

Solution:

(LCM of 4 and 5 is 20, so will we convert each fraction into an equivalent fraction with denominator 20)

Rahul takes less time,

Question: 9

A piece of a wire 7/8 metres long broke into two pieces. One piece was 1/4 meter long. How long is the other piece?

Solution:

Length of the wire = 7/8 metres

Length of one piece of wire = 1/4 metres

Let the length of the second piece of wire be x m.

Therefore, Length of the wire = length of one piece + length of the second piece

Therefore, the length of the second piece is 5/8 metres

Question: 10

 Shikha and priya have bookshelves of the same size shikha’s shelf is 5/6 full of book and priya’s shelf is 2/5 full. Whose bookshelf is more full? By what fraction?

Solution:

Fraction of shikha’s filled bookshelf = 5/6

Fraction of Priya’s filled bookshelf = 2/5

Comparing 5/6  and 2/5, we get :

LCM of 5 and 6 is 30, so will convert each fraction into an equivalent fraction with denominator 30.

Shikha’s shelf is more full.

Therefore,

Question: 11

Ravish’s house is 9/10 Km from his school. He walked some distance and then took a bus for 1/2 Km. How far did he walk?

Solution:

Total distance between the house and the school = 9/10 Km

Distance covered in the bus = 1/2 Km

Distance covered by walking + distance covered in the bus = total distance between

the house and the school

Distance covered by walking = total distance between the house and the school – Distance

covered in the bus

Distance covered by walking:

9/10 Km – 1/2 Km

LCM of 10 and 2 is 10, so we convert each fraction into an equivalent fraction with denominator 10

(HCF of numerator and denominator is 2)