1: you turn %15 into a decimal by moving the decimal point two places to the left.
2: and then you multiply .15 by 1,200 , which will get you 180.00
3: from there you will add 180 to 1,200
4: which will get you 1,380
hope it *im kind of slow so idk if my answer is right*
honestly bro aint no one got time to answer these dumb question just do it p***y