[ Percentage and ratio problems ]

After the crisis, all prices increased by $25 \%$. By what percentage fewer goods can be bought with the same salary?

#
An increase in prices by $25 \%$ means that the new price of a product is equal to the old price multiplied by $5 / 4$. Therefore, with the previous salary, one can buy

$1:{ }^{5} / 4=4 / 5$ of the old quantity of goods, which is $20 \%$ less.

## Answer

$20 \%$ less.