Question

Mike's Bikes has mountain bikes that usually sell for $275 on sale for $220. Mike used this ratio to find the percent change. Is he correct? Explain.

Answer 1

No. Mike wrote the ratio as the amount of change to the new amount. He should have used the ratio of the amount of change to the original amount, which is 55

55/275 , or 20%.

Answer 2

20%
220 divided by 275 to get .8 
80% then 80% minus 100%
=20%