Find the geometric mean of the following number : 18,40,25 and 45.

Explanation

We have total number of numbers is 4.
`therefore ` Geometric mean `=(18xx40xx25xx45)^((1)/(4))={(3xx3xx2)xx(2xx2xx2xx5)xx(5xx5)xx(5xx3xx3)}^((1)/(4))`
`=(3^(4)xx2^(4)xx5^(4))^(1/4)=3xx2xx5=30`