Question

If the mean of five numbers is 25, what is their sum?

Answer 1

`125`

Explanation:

Mean is defined as (sum of values)/(number of values).

The five values can be anything, as long as they add up to `125`, because then the mean will be: `125//5=25`.

`25,25,25,25,25` will do (obviously), but also:
`1,1,1,1,121`

The second example, by the way, is a good illustration of why the mean is not always a good measure, if you want to say something about a collection of data.