If the price of salt decreases by 20%, then by what percentage should consumption be increased to keep the expenditure same?

Question

Question

This question was previously asked in

SSC CGL 2022 Tier-I Official Paper (Held On : 03 Dec 2022 Shift 3)

Answer 1

Given:

The price of salt decreases by 20%.

Calculation:

Let the original price of 100 units of salt be Rs. 100.

Now the price of 100 units of salt = 100 - 100 × 20% = Rs. 80

Now the quantity of salt one can get for Rs. 100 = 100/80 × 100 = 125 gm

Now, % increase in consumption = \(\frac {125 - 100}{100} × 100\%\) = 25%

∴ By 25% the consumption should be increased to keep the expenditure the same.

Shortcut Trick

the price of salt decreases by 20%, Before : After = 5 : 4

To make the expenditure same, Consumption must be Before : After = 4 : 5

So, consumption increased by 1/4 × 100 = 25%