Question

F is inversely proportional to `sqrtg` when f=15, g=144. How do you work out g when f=90?

Answer 1

`g=4`

Explanation:

As `f` is inversely proportional to `sqrtg`,

it means `fprop1/sqrtg`

i.e. `f=k/sqrtg`, where `k` is a constant

When `f=15`, `g=144`

Hence `15=k/sqrt144=k/12`

and `k=12xx15=180`

Hence equation is `f=180/sqrtg` and when `f=90`,

we have `90=180/sqrtg`

or `sqrtg=180/90=2`

and `g=4`