Answer:
$5.40
Step-by-step explanation:
First, find Dave's purchase. To do this, you multiply 15 by the tax percent and add that to the original.
So:
15 x 8% = 15 x 0.08 = 1.2
15 + 1.2 = 16.2
Next, do the same for Mel's purchase:
20 x 8% = 20 x 0.08 = 1.6
20 + 1.6 = 21.6
Then, you subtract Dave's purchase from Mel's:
21.6 - 16.2 = 5.4
This comes out to $5.40
