The price of a certain item is increased by 15%. If consumer wants to keeps his expenditure on the item same as before, how much percent must he reduce his consumption of that item ?

Correct Answer: $$13\frac{1}{{23}}\% $$
Reduction in consumption :
$$\eqalign{ & = \left\% \cr & = \left( {\frac{{15}}{{115}} \times 100} \right)\% \cr & = \frac{{300}}{{23}}\% \cr & = 13\frac{1}{{23}}\% \cr} $$