Question

How to find mean proportional between two numbers?

Answer 1

There are various uses of the square root, one of which is to find a mean proportional between any two numbers, which is performed thus: Multiply the two given numbers together, then extract the square root out of their product, and it will be the mean proportional sought.

Ex. 1. To find a Mean Proportional between 3 and 12.

Here 3 x 12=36.

And √36 is 6, the mean proportional sought.

For 3∶6∷6∶12.