Answer:
12
Explanation:
The greatest common factor is the biggest number that is divisible by both of the terms 24x and 60y.
Obviously, given that we have two variables, neither x nor y can be included in the GCF, so it must be simply a constant. Now, looking at the list of numbers, we see that the biggest number they share is 12.
Thus, the GCF of 24x and 60y is 12.
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