A shirt's price was increased by 10% and then decreased by 10%. If the final price is $99, what was the original price of the shirt?

✓ Correct Answer: Option A

Let the original price be P. An increase of 10% makes it 1.10P. A decrease of 10% on the new price makes it (1.10P) * 0.90 = 0.99P. If 0.99P = $99, then P = $99 / 0.99 = $100.