Answer the following question, with explanation first.
Mark hires a singer for 3 hours at $15 an hour. He then tips the singer 20%. How much did he pay?

54
The cost was 15 * 3 = $45.

So the tip was 45 *.

2 = $9.

So in total, he paid 45 + 9 = $54.

.

Final answer: 54