The price s of a sweater is reduced by 25% for a sale. after the sale, the reduced price was increased by 20%. what is the final price of the sweater?

For simplicity, let's say that the original price of the sweater was $100.
It was initially reduced by 25%, which is $25, Hence, the sweater is now $75.
Then, this price was increased by 20% of 75. You can divide 75 by ten and then multiply by two to give 15. We then add this to 75 to give $90.
Therefore, we can say that the final price of the sweater is 90% of the original price.