It takes 17 full specific type of trees to make one tonne of paper. If there are 221 such trees in a forest, then
i. what fraction of forest will be used to make (a) 5 tonnes of paper (b) 10 tonnes of paper
ii. To save 7/13 part of the forest how much of paper we have to save

Solution:

i. Number of trees required to make 1 tonne of paper = 17

Total number of trees = 221

Fraction of forest will be used to make one tonne of paper = 17/221 = 1/13

a. Fraction of forest will be used to make 5 tonnes of paper = 1/13 × 5 = 5/13

b. Fraction of forest will be used to make 10 tonnes of paper = 1/13 × 10 = 10/13

ii. Let us assume that we have to save x tonnes of paper to save 7/13 part of the forest

Fraction of forest will be used to make x tonnes of paper = 1/3 × x = x/13

x/13 = 7/13

x = 7/13 × 13 = 7

✦ Try This: Simplify: [2(2/3) + 25/15] / [2(2/4) ÷ 1/8]

To solve the above problem you can follow the fractions and decimals rules to get the required answer.

☛ Also Check: NCERT Solutions for Class 7 Maths Chapter 2

NCERT Exemplar Class 7 Maths Chapter 2 Exercise Problem 105

It takes 17 full specific type of trees to make one tonne of paper. If there are 221 such trees in a forest, then: i. what fraction of forest will be used to make (a) 5 tonnes of paper (b) 10 tonnes of paper, ii. To save 7/13 part of the forest how much of paper we have to save

Summary:

5/13 fraction of forest will be used to make 5 tonnes of paper and 10/13 fraction of forest will be used to make 10 tonnes of paper.

To save 7/13 part of the forest we have to save 7 papers.

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