How to find percent of change

my 7th grader has mathhomework and he needs to find the percent of change in two numbers. example 15 yards to 18 yards. what is the percentage difference?
Asked Dec 15, 2013
20% trust me same homework GOT IT RIGHT :p thats # 1 anyway

how I got the awnser_

18-15=3 divided by 12 =0.20=20 good luck

Answered Feb 10, 2014
Edited Feb 10, 2014
That’s completely wrong
Answered Nov 26, 2018

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