Respuesta :

bobeld
One way is to make 5 the 3rd number in a series of equally spaced numbers:

3,4,5,6,7 = mean of 5

1, 3,  5,  7,  9 = mean of five

4,  4.5,  5,  5.5,  6 = mean of five

4.8,  4.9,  5.0, 5.1, 5.2  = mean of five
Do you get the idea?
AL2006

If their mean is 5, then the numbers add up to 25.
Here are a few sets that do the job:
 
1, 2, 3, 4, 15

10, 20, 30, 40, -75

+2,  -2,  +99,  -99,  25

1,  5,  5,  5,  9