eli5 The percentage rule

Question

Can someone explain how/why X% of Y is equal to Y% of X? I know it’s true but I can’t figure out why. Thanks!

In: 10

Answer 1

X% of Y = Y% of X. A percentage is a multiplication. Like 69% of 70 = 70×0.69. So:

Y × X/100 = X × Y/100 //×100

Y × X = X × Y

True because multiplication is commutative.

Answer 2

X% of Y = Y% of X. A percentage is a multiplication. Like 69% of 70 = 70×0.69. So:

Y × X/100 = X × Y/100 //×100

Y × X = X × Y

True because multiplication is commutative.