10 coins. 70 divided by 7equals 10
GCF means the term(s) that 6x and x have.
The GCF is x because:
1. Using multiplication: 6x * x = 6x^2
becomes x(6+x) = 6x^2
GCF is x.
Good luck to you!

Method 1.
Use 

Method 2.

The solution to this equation is the number 8
Every time you play a song 8 different songs can be played, since you do this 3 times:

Or, an easier way to write this if play them many times:

In which the 8 is how many options and the 3 how many times you play.