find the greatest common factor of 24 and 42.

Explanation:

Step1: Prime - factorize 24

$24 = 2\times2\times2\times3$

Step2: Prime - factorize 42

$42=2\times3\times7$

Step3: Identify common factors

The common prime factors are 2 and 3.

Step4: Calculate GCF

The GCF is $2\times3 = 6$.

Answer:

6