Solution:
we are given that
Howard is saving to buy a mountain bike that costs $245, excluding tax.
He already has saved $28.
we have been asked to find
Howard must save each week so that at the end of the 9th week.
Money required to save in 9 weeks

So Money required to save each week

This is the amount that he must save to reach $245, excluding Taxes.
Hence to have enough money, he should save $25 per week, so that he can pay the taxes as well.