Solve m=9/5p +18 for p , if possible show steps

The square pyramid has a volume of 441 cubic inches. what is the value of x? 1/7x is the height x is the base

Having a hard time understanding this question (see attachment).

Melanie is buying a bathing suit that costs 39.99. she is given a discount at the cash register of $6.00 when she scratched 15% off on a game piece for a store promotion. what will the sale price of melanie’s bathing suit be?