Question

The sales tax in Kadisha's state is 5%. Kadisha says she computes a 15% tip by multiplying the tax shown on her bill by 3. For a bill with a tax charge of $.38, Kadisha's tip is $.38 times 3 = $1.14. Why does Kadisha's method work?

Answer 1

Explanation:

Kadisha's method works because 15% is 3 times 5%, and both amounts are computed on the amount of the bill before tax is added.