Question

An increase from 16 to 20 is what percent of increase?

Answer 1

25%

Explanation:

Your measure start at 16. So that is the basis (unless stated otherwise) upon which you reference the change.

That is: `(20-16)/16` is you fraction.

This gives: `4/16 -> (4-:4)/(16-:4) =1/4`

For this to be a percentage we need the denominator such that it becomes 100. Thus we have:

`1/4 ->(1/4xx1) ->(1/4xx25/25)=25/100`

To express this in the standard script form we have 25%

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Foot note:

Sometimes the use of % and its meaning is misunderstood.
The % that follows the 25 really means that we have 25 parts out of 100. In other words: `25/100`

To coin a phrase; 25% and `25/100` are 'one and the same thing'.