CBSE Important Questions Class 7 Maths Chapter 8 Working with Fractions

CBSE Important Questions Class 7 Maths Chapter 8 – Working with Fractions

Class 7 Maths Chapter 8 Working with Fractions is a chapter of the new NCERT (National Council of Educational Research and Training) textbook Ganita Prakash. It teaches students how to multiply and divide fractions, how to find a fraction of a quantity, how to use reciprocals, and how to change between improper fractions and mixed numbers. These skills are used every day when we share, measure and compare things.

These CBSE important questions for Class 7 Maths Chapter 8 include multiple choice questions, reciprocal and product questions, and word problems on lace, ribbon, flour, money, land, milk, bottles and a robotic cleaner. Every question has a clear step-by-step answer in simple English, so students can practise on their own, parents can check the working, and teachers can use them in class. A free printable PDF of these important questions is also available on this page.

CBSE Important Questions Class 7 Maths Chapter 8 Working with Fractions

CBSE Important Questions Class 7 Maths Chapter 8 Working with Fractions

Q1. For each of the questions below, choose the expression that describes the solution. Then simplify it.
(a) Maria bought 8 m of lace to decorate the bags she made for school. She used 1/4 m for each bag and finished the lace. How many bags did she decorate?
(i) 8 × 1/4 (ii) 1/8 × 1/4 (iii) 8 ÷ 1/4 (iv) 1/4 ÷ 8
(b) 1/2 metre of ribbon is used to make 8 badges. What is the length of the ribbon used for each badge?
(i) 8 × 1/2 (ii) 1/2 ÷ 1/8 (iii) 8 ÷ 1/2 (iv) 1/2 ÷ 8
(c) A baker needs 1/6 kg of flour to make one loaf of bread. He has 5 kg of flour. How many loaves of bread can he make?
(i) 5 × 1/6 (ii) 1/6 ÷ 5 (iii) 5 ÷ 1/6 (iv) 5 × 6

Answer: (a) To find the number of bags, divide the total lace by the lace used for one bag: 8 ÷ 1/4. The correct expression is (iii).
8 ÷ 1/4 = 8 × 4 = 32 bags.
(b) To find the ribbon for one badge, divide the total ribbon by the number of badges: 1/2 ÷ 8. The correct expression is (iv).
1/2 ÷ 8 = 1/2 × 1/8 = 1/16 metre.
(c) To find the number of loaves, divide the total flour by the flour needed for one loaf: 5 ÷ 1/6. The correct expression is (iii).
5 ÷ 1/6 = 5 × 6 = 30 loaves.

8 m of lace divided into 1/4 m pieces gives 32 pieces

Q2. What is the reciprocal of (−1/3) × (−15/6)?
(a) −6/5
(b) 5/18
(c) 6/5
(d) 5/6

Answer: (c) 6/5
First find the product: (−1/3) × (−15/6) = 15/18 (a negative number times a negative number is positive). Simplify: 15/18 = 5/6.
The reciprocal of 5/6 is 6/5.

Q3. Ria had ₹3650 in her bank account. She used half of her money to buy gifts for her sister and 3/4 of the remaining money to buy clothes for herself. How much money is left with her?

Answer: Step 1: Money at the start = ₹3650
Step 2: Money spent on gifts = 1/2 × 3650 = ₹1825. Remaining = 3650 − 1825 = ₹1825
Step 3: Money spent on clothes = 3/4 × 1825 = 5475/4 = ₹1368.75
Money left = 1825 − 1368.75 = ₹456.25 = ₹456 1/4
Ria is left with ₹456 1/4 (₹456.25).

Bar graph of Ria's money at each step

Q4. A farmer uses 2/3 of his land for vegetables. He uses 5/8 of that area for tomatoes. What fraction of his total land is used for tomatoes, in the lowest form?
(a) 5/11
(b) 10/24
(c) 5/12
(d) 15/24

Answer: (c) 5/12
Fraction of land for tomatoes = 5/8 of 2/3 = 5/8 × 2/3 = 10/24 = 5/12 in the lowest form.

Q5. A bamboo grows 5/6 metres in a day. How much does it grow in 9 days, and what is the simplified mixed number form of the answer?
(a) 7 1/2
(b) 1 4/5
(c) 15/7
(d) 2 1/2

Answer: (a) 7 1/2
Growth in 9 days = 9 × 5/6 = 45/6 = 15/2 m.
As a mixed number, 15/2 = 7 1/2 m. So the bamboo grows 7 1/2 metres in 9 days.

Q6. Rohani paints for 2 3/7 hours every day and takes 15 days to paint the entire wall. How many hours did she take to paint the wall?

Answer: Total hours = hours per day × number of days = 2 3/7 × 15
2 3/7 = (2 × 7 + 3)/7 = 17/7
17/7 × 15 = 255/7 = 36 3/7
Rohani took 36 3/7 hours to paint the wall.

Q7. The cost of one litre of milk is ₹16 3/5. What is the cost of 12 1/2 litres of milk?
(a) ₹128 1/2
(b) ₹167 1/2
(c) ₹207 1/2
(d) ₹212 1/2

Answer: (c) ₹207 1/2
Cost of 1 litre = 16 3/5 = 83/5. Quantity = 12 1/2 = 25/2 litres.
Total cost = 83/5 × 25/2 = 83 × 5/2 = 415/2 = ₹207 1/2.

Q8. What is the reciprocal of 1?

Answer: The reciprocal of a number is found by flipping it. 1 can be written as 1/1, and flipping 1/1 gives 1/1 = 1. So the reciprocal of 1 is 1.

Q9. Product of 11/12 × 16/4 × 9/16 is
(a) 2 1/16
(b) 3/4
(c) 1/4
(d) 1 1/2

Answer: (a) 2 1/16
11/12 × 16/4 × 9/16 = (11 × 16 × 9)/(12 × 4 × 16). Cancel 16: (11 × 9)/(12 × 4) = 99/48 = 33/16.
33/16 = 2 1/16.

Q10. The given fractions are 1/2, 4/5, 7/8. If the numbers are arranged in the ascending order or descending order, then the middle number is
(a) 1/2
(b) 7/8
(c) 4/5
(d) 3/5

Answer: (c) 4/5
Convert to decimals: 1/2 = 0.5, 4/5 = 0.8, 7/8 = 0.875. In ascending order: 0.5, 0.8, 0.875. The middle number is 0.8 = 4/5.

Q11. A square has an area of 1 square unit. A small square inside it covers 1/3 of its area. A triangle occupies 3/5 of this small square. Find the fraction of the whole square occupied by the triangle.

Answer: Fraction of the whole square covered by the triangle = 1/3 × 3/5 = 3/15 = 1/5
So 1/5 of the square is occupied by the triangle.

Square showing 1/3 part and a triangle covering 3/5 of it

Q12. You are given 3/4 litre of a herbal concentrate. You need to pack it into bottles of 1/8 litre each. If one bottle is dropped and wasted after packing, how many full bottles are left?

Answer: Total bottles filled = 3/4 ÷ 1/8 = 3/4 × 8 = 6 bottles
One bottle is wasted, so 6 − 1 = 5 full bottles are left.

Q13. A robotic cleaner can clean 3/8 of a room in 45 minutes. At the same rate, how much of the room can it clean in 1 hour 15 minutes?

Answer: Time for 3/8 of the room = 45 min
Time for the full room = 45 ÷ 3/8 = 45 × 8/3 = 15 × 8 = 120 minutes
1 hour 15 minutes = 75 minutes
Fraction of the room cleaned in 75 minutes = 75/120 = 5/8

Fraction bars showing 3/8 of the room in 45 min and 5/8 in 75 min

Q14. If 3/4 of a number is 9/10, what is the number?

Answer: Let the number be x. Then 3/4 × x = 9/10
x = 9/10 ÷ 3/4 = 9/10 × 4/3 = 36/30 = 6/5
Hence, the number is 6/5.

Related Study Material on Extramarks