NCERT Class 7 Mathematics Solutions: Chapter 8 –Comparing Quantities Exercise 8.3 Part 4

Get unlimited access to the best preparation resource for JEE/Mains Mathematics: fully solved questions with step-by-step explanation- practice your way to success.

Download PDF of This Page (Size: 156K)

Different Formula are given

Different Formula Are Given

1. Juhi sells a washing machine for. She loses in the bargain. What was the price at which she bought it?


Selling price of washing machine

Loss percent

Consider the cost price of washing machine be .

Loss = Loss% of C.P


So, the cost price of washing machine is .


(i) Chalk contains Calcium, Carbon and Oxygen in the ratio. Find the percentage of Carbon in chalk.

(ii) If in a stick of chalk, Carbon is , what is the weight of the chalk stick?


(i) Given ratio

Total part

Part of Carbon

Percentage of Carbon part in chalk

(ii) Quantity of Carbon in chalk stick

Consider, the weight of chalk be .


So, the weight of chalk stick is .