SBI PO – 2015 – 12

Question: The price of sugar rises by 25%. By what percent a person must reduce the consumption, so as not to increase the expenditure? 

[चीनी के मूल्य 25% की वृद्धि हो जाने पर उसकी खपत में कितने प्रतिशत की कमी कर दी जाये कि उसका खर्च न बढ़े?]

Solution:

Detailed Explanation: First Method: Initial Expenditure of a certain quantity of sugar =Rs 100

After increase of 25% in the price of sugar, the new price of sugar of the same quantity =Rs 125

If the expenditure is not to be increased, then the sugar of Rs. 25 should be reduced out of sugar of Rs. 125, which is one fifth, that is 20%. Ans.   

Second Method: When any quantity is changed by x% and y% successively, then the quantity is changed by

Therefore, the required percentage reduction of sugar is 20%. Ans.]