Question

Emma went out shopping with her father and bought a dress that cost $40.00. In class, she

learned to find the sales tax by multiplying by .08 (the sales tax in her state is 8%). Emma
found the tax, and then added the tax to the original amount. Emma's mother suggested that
she should just multiply the cost of the dress by 1.08 and that this method would give her the
final answer with the tax included. Emma was confused. Who is right? Work it out both ways
and explain your thinking.

Answer 1

Both ways are correct

If you multiply the cost by 8% and add, you will still get 108% as your total.

Answer 2

Both ways are correct

Explanation:

Father's way is ( 40 × 0.08 ) + 40 = $43.2

Mothers way is 40 × 1.08 = $43.2