How do I calculate a percentage increase? For example; there are 15 fish in a fish tank, after a year they have bred and now there are 20 fish in the tank. By what % has the number of fish increased?

Original value = 15 New Value = 20 Difference = New value - original value 20 - 15 = 5
(Difference / original) x 100(5/15) x 100 = 33.3%

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Answered by Seyi A. Maths tutor

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