Question

What is the average of 1/20 and 1/30?

Answer 1

Average of `1/20` and `1/30` is `1/24`.

Explanation:

Average of two numbers is half of their sum.

As the two numbers are `1/20` and `1/30`, their sum is

`1/20+1/30`

= `(1×3)/(20×3)+(1×2)/(30×2)`

= `3/60+2/60`

= `5/60=(1×5)/(12×5)`

= `(1×cancel5)/(12×cancel5)`

= `1/12`

As average is half of sim of two numbers,

Average of `1/20` and `1/30` is

`1/2×1/12=1/(2×12)=1/24`