Okay, so we need to find the price of the original shirt and the discounted shirt with the 5% tax.
5% (into a real number) is .05
Multiply 20.98 and 15.48 by .05
20.98*.05= 1.049 I am going to round to 1.05
15.48*.05= 0.774 I am going to round to .75
Now we know the prices of both, so we subtract them by each other.
20.98+1.05= 22.03
15.48+.75= 16.23
22.03-16.23= 5.80
But since we rounded the numbers, I would go with choice D.
Hope this helps!