Answer:
2c
Explanation:
The greatest common factor is the biggest number that divides into different numbers.
The greatest common factor between 4c and 10c is the biggest number you can divide each of them by to get a whole number.
Since c is in both of them that means that it is going to be #c
The biggest number you could divide 4 and 10 by is 2
4/2 = 2
10/2 = 5
So the GCF between 4c and 10c is 2c