Question

The brain represents 3/40 of an average person's weight. what percent is this?

Answer 1

You can calculate this percentage by setting up a proportion like this. Note that percent is the amount per 100:


`(3)/(40) = (x)/(100)`

Use cross multiplication:


`(3)/(40) = (x)/(100) \\ \\ 3*100 = 40*x \\ \\ 300 = 40x \\ \\ (300)/(40) =x \\ \\ x = 7.5`

The brain represents 7.5% of an average person's weight.