The greatest common factor (GCF) is also known as greatest common divisor (GCD).
First we have to find the prime factorization of 60
60 = 2² × 3 × 5
Then we have to find the prime factorization of 45
45 = 3² × 5
Now we have to multiply the common factors to both numbers with a lower exponent
GCF = 3 × 5 = 15
Answer : GCF(60,45) = 15
Hope this helps!
[tex]\textit{\textbf{Spymore}}[/tex]