What is 10 percent off 21.99?

To calculate 10 percent off $21.99, first find 10 percent of the amount by multiplying $21.99 by 0.10, which equals $2.199. Subtract this discount from the original price: $21.99 - $2.199 = $19.791. Therefore, 10 percent off $21.99 is approximately $19.79.