How much is percent increase from 200 to 320

A change from 200 to 320 represents a positive change (increase) of 60%Use the formula found below on this webpage to find the percent change by replacing the given values:Percent change = [(200 - 320) / 200] x 100 = 60 % (increase)Where: 200 is the old value and 320 is the new value. In this case we have a positive change (increase) of 60 percent because the new value is greater than the old value. 
Your Answer Is 60%

The answer should be b.

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