The total cost is 35.79 I believe because you need to find the percentage of the tax and the tip then add it to the total. You can find a percentage by multiplying the percentage and the total together and then dividing it by 100. Then you just add them all together. 28.35+1.77(that’s the tax 28.35*6.26/100)+5.67(The tip 20.35*20/100)=35.79 (if someone wants to check that go ahead I might have plugged the numbers into my calculator incorrectly)