NCERT Solutions for Class 8 Maths - Fractions (Exercise 7.4, 7.5 and 7.6)

Exercise 7.4

Q1. Write the shaded portion as a fraction. Arrange them in ascending and descending order using correct sign ‘<’, ‘=’, ‘>’ between the fractions:
(a)
(b)  
(c) Show  on the number line. Put appropriate signs between the fractions given.

Ans:

Ascending order:  
Descending order:  

Ascending order:  
Descending order:
(c) Number line

Q2. Compare the fractions and put an appropriate sign.

Ans:

Q3. Make five more each pairs and put appropriate signs. 
Ans:

Q4. Look at the figures and write ‘<’ or ‘>’ between the given pairs of fractions.

Make five more such problems and solve them with your friends. 
Ans:





Five more such problems:





Ans:

Q5. How quickly can you do this? Fill appropriate sign (‘<’, ‘=’, ‘>’)











Ans:

Q6. The following fractions represent just three different numbers. Separate them into three groups of equivalent fractions, by changing each one to its simplest form.
(a) 2/12
(b) 3/15
(c) 8/50
(d) 16/100
(e) 10/60
(f) 15/75
(g) 12/60
(h) 16/96
(i) 12/75
(j) 12/72
(k) 3/18
(l) 4/25
Ans:












Equivalent groups:

Q7. Find answers to the following. Write and indicate how you solved them.
(a)  
(b) 
(c) 
(d) 
Ans:

  [∴ L.C.M. of 9 and 5 is 45]


   [∴ L.C.M. of 16 and 9 is 144]


   [∴ L.C.M. of 5 and 20 is 100]


 [∴ L.C.M. of 15 and 30 is 30]

Q8. Ila read 25 pages of a book containing 100 pages. Lalita read 2/5 of the same book. Who reads less?
Ans: Ila read 25 pages out of 100 pages.
Fraction of reading the pages =  25/100 = 1/4 th part of the book
Lalita read 2/5 th part of the book  = 40/100 pages

Therefore, Ila read less.

Q9. Rafiq exercised for 3/6 of an hour, while Rohit exercised for 3/4of an hour. Who exercised for a longer time?
Ans: Rafiq exercised 3/6 of an hour.
Rohit exercised 3/4 of an hour.

Therefore, Rohit exercised for a longer time.

Q10. In class A of 25 students, 20 passed in first class; in another class B of 30 students, 24 passed in first class. In which class was a greater fraction of students getting first class?
Ans: In class A, 20 passed out of 25, i.e., 20/25 = 4/5
In class B, 24 passed out of 30, i.e., 24/30 = 4/5
Hence, each class have the same fraction of student getting a first class.

Exercise 7.5

Q1. Write these fractions appropriately as additions or subtractions:
(a)
(b) 
(c) 
Ans:

Q2. Solve:









Ans:

Q3. Shubham painted 2/3of the wall space in his room. His sister Madhavi helped and painted 1/3 of the wall space. How much did they paint together?
Ans: Fraction of wall painted by Shubham = 2/3
Fraction of wall painted by Madhavi = 1/3
Total painting by both of them =
Therefore, they painted the complete wall.

Q4. Fill in the missing fractions.

Ans:
(a) 4/10
(b) 8/21
(c) 6/6
(d) 7/27

Q5. Javed was given a basket of oranges. What fraction of oranges was left in the basket?
Ans:
Total = 1
Fraction of Orange left  

Thus, 2/7 oranges were left in the basket.

Exercise 7.6

Q1. Solve














Ans:
(a) L.C.M. of 3 and 7 is 21

(b) L.C.M. of 10 and 15 is 30

(c) L.C.M. of 9 and 7 is 63
 
(d)
 
(e)

(f)

(g)

(h)

(i)

(j)

(k)

(l)

(m)

(n)

Q2. Sarita bought 2/5 metre of ribbon and Lalita 3/4 metre of ribbon. What is the total length of the ribbon they bought?
Ans: Ribbon bought by Sarita = 2/5 m and Ribbon bought by Lalita = 3/4 m
The total length of ribbon =

Therefore, they bought    of ribbon.

Q3. Naina was given  piece of cake and Najma was given  piece of cake. Find the total amount of cake was given to both of them.
Ans: Cake taken by Naina =  piece and Cake taken by Najma  piece
Total cake taken

Therefore, the total consumption of cake is  

Q4. Fill in the boxes: 



Ans:

Q5. Complete the addition-subtraction box.

Ans:

Q6. A piece of wire 7/8 metre long broke into two pieces. One piece was 1/4 metre long. How long is the other piece?
Ans:
The total length of wire = 7/8 meter
Length of first part = 1/4 meter
Remaining part     [∴ L.C.M. of 8 and 4 is 8]

Therefore, the length of the remaining part is 5/8 meter.

Q7. Nandini’s house is 9/10 km from her school. She walked some distance and then took a bus for 1/2 km to reach the school. How far did she walk?
Ans:
The total distance between school and house 9/10 km
Distance covered by bus = 1/2 km
Remaining distance  [∴ L.C.M. of 10 and 2 is 10]

Therefore, the distance covered by walking is 2/5 km.

Q8. Asha and Samuel have bookshelves of the same size partly filled with books. Asha’s shelf is 5/6 th full and Samuel’s shelf is 2/5 th full. Whose bookshelf is more full? By what fraction?
Ans:

⇒   [∴ L.C.M. of 6 and 5 is 30]
∴    
⇒  
∴ Asha’s bookshelf is more covered than Samuel.


Q9. Jaidev takes minutes to walk across the school ground. Rahul takes 7/4 minutes to do the same. Who takes less time and by what fraction?
Ans:
Time taken by Jaidev =  minutes = 11/5 minutes
Time taken by Rahul =  7/4 minutes
Difference   [∴ L.C.M. of 5 and 4 is 20]

Thus, Rahul takes less time, which is 9/20 minutes.