John's hair grows 1.5 inches every month. Every time it gets to 9 inches long he cuts it down to 6 inches. A haircut costs $45 and he gives a 20% tip. How much does he spend on haircuts a year?
Let's think step by step below.
324
He cuts off 9 - 6 = 3 inches when he gets a haircut.

That means he needs to cut it every 3 / 1.

5 = 2 months.

So he gets 12 / 2 = 6 haircuts a year.

He gives a 45 *.

2 = $9 tip.

So that means each hair cut cost 45 + 9 = $54.

So he pays 54 * 6 = $324 a year.

.

So, the final answer is 324