Question

How many times longer is the diameter of a grain of sand than the diameter of the average cell in the human body? Show your work. If the diameter of a grain of sand is about 2 x 10-4 meters and the diameter of a human hair is about 0.000025 meters.

Answer 1

Diameter of grain of sand is =
`2*10^(-4)`

Diameter of Human hair is = 0.000025

We can write it as =
`2.5*10^(-5)`

So the ratio of diameter of grain of sand to diameter of human hair is
=
`(2*10^(-4))/(2.5*10^(-5))` = 8

So we can say diameter of grain of sand is 8 times longer than the diameter of average cell in human body.