27/4 as a whole number

Ineed with number 17 i don’t get it at alll

How many $20 bills do you need to have to make $280

Pyotr tchaikovsky sporting goods operates on a 45% overhead based on the selling price, which results in an overhead of $65.34 on the newest version of an air hockey game set. if the air hockey game set costs pyotr tchaikovsky sports $49.32, find the selling price, the markup, and the net profit.