20 can be broken down to 4 times 5
then 4 can be further broken down to 2 times 2
therefore your answer is A 2^2x5
Work: 5,5,5,10,20
Add
5+5+5+10+20
10+5+10+20
15+10+20
25+20
45
÷ by the amount of numbers
45÷5=9
Ansser: mean=9
The least common factor of x and x squared is x
