Answer: 
Total: $25.5
Explanation: 
The total amount is 
Total = discounted price + tip 
Now the discounted price after 15% coupon is 100% - 15 % = 85% of the original price; therefore, 

Hence, the discounted price is found to be $21.25. 
Now we find the tip amount. 
The tip amount is 20% of the discounted price; therefore, 

Thus we find that the tip amount is $4.25. 
Therefore, the total is 
 Total = $21.25 + $ 4.25 = $ 25. 5
Whichi s our answer!