Answer:
1) The 15%-off coupon is $3.
2) The cost of the meal after the discount is $17.
3) The final cost of the meal with taxes is $18.19.
Step:
1) To find the discount, try to find the amount of 1%, (20÷100 x 15 = 3)
2) To find the cost of the meal after discount (20-3 = 17)
3) To find the final cost, try find the taxes amount (17÷100 x 7 + 17 = 18.19)