For 20 points show me steps for answering this question !
tiffany’s pay varies directly with the number of hours that she works. if she earned $77.28 for 4 h of work, how much will she earn for 15 hours of work

To answer this first we need to find out how much Tiffany earns per hour and then we will multiply. lets do it:-

77.28 ÷ 4 = 19.32
$19.32 per hr

CHECK OUR WORK:-
19.32 × 4 = 77.28
we were RIGHT!!

Now lets see how much she earns in 15 hrs.

19.32 × 15 = 289.8
Tiffany earns $289.8 to work for 15 hrs.

CHECK OUR WORK:-

289.8 ÷ 15 = 19.32
we were RIGHT!!

So, Tiffany earns $289.8 to work for 15 hrs.

Hope I helped ya!! 

Divide 77.28 by 4. Multiply the answer by 15. =(15)(19.32)=289.8

The answer is the third choice