The shoe store's clerks are paid on commission. If the clerk receives a 12% commission on total purchase amounts before tax is applied, how much would the commission be for Issac's purchase with a coupon?

a) 37 + 42 = 79

=7/100 x 79

=553/100

=5.53

Isaac's total bill = 79 + 5.53 = $84.53

b) 25/100 x 79

= 19.75

= 79 - 19.75

= $59.25 (before tax)

7/100 x 59.25

= 414.75/100

= 4.15

= 59.25 + 4.15

= $63.4 (after adding tax)

First we have to take out the percentage of discount and minus it from the total cost. To find the discounted price with tax, we have to take out the percentage of the tax from the discounted amount and add it to the discounted amount to get the total cost.