Question

A house-owner was getting his house painted. He was advised that he would require 30kg of paint. Allowing for 10% wastage and assuming that the paint is available in 3kg cans, what would be the cost of paint purchased, if one can cost Rs. 20?

Answer 1

Hint: In the above given question, calculate the amount of paint in one can which could be successfully used. Then, calculate the total number of cans to be used, multiplying it with the cost of one can will provide you with the cost of the total paint purchased.

Complete step-by-step answer:
We are given that one can contain 3kg of paint and there is a wastage of 10%.
Therefore, the paint which can be successfully used is given as
10% of 3 kg
$ = 3 \times \dfrac{{10}}{{100}}$
$ = \dfrac{{3}}{{100}}$
=0.3 kg
So, the paint in one can be given as= (3-0.3) kg
=2.7 kg
Since, it is given that 30 kg of paint is required.
The number of cans needed$ = \dfrac{{30}}{{2.7}}$
=11.11
=11 cans (approx.)
The cost of 1 can = Rs 20
So, the cost of 11 cans$ = 11 \times 20$
= Rs 220
Therefore, the cost of paint purchased would be Rs 220.
Hence, the correct answer is the option $(d)$.

Note: Do not forget to subtract the paint allowed for wastage from the total paint in a can. Then calculate the total number of cans required using this new amount of paint in a can and thus you will reach at the required solution.