The mean of a set of five numbers is 4.8. Given that the sixth number is x and the mean of these six numbers is 5.5, find the value of x.

Given that the mean of the five numbers is 4.8, the total of the numbers will be:

5*4.8

=24

after adding x, the total will be:

(24+x)

the mean will be:

(24+x) / 6=5.5

solving for x we get:

24+x=33

hence

x=33-24

x=9

The sixth number is 9