If the side of a square is doubled in size to 8", by what percent did it's area increase?

Answer 1

area square=s^2
if doubled, area= (2s)^2=4s^2

percent= changeInArea/area * 100
= 400/1=four hundred percent

Answer 2

If the result is 400% of the original 100%, then the increase is 300%

+100% = doubled
+200% = tripled
+300% = quadrupled

Answer 3

That is always confusing and the thing to remember is that doubling is 100% increase.