Quantitative Reasoning of two numbers?

Question

Hello, my question is "All numbers that are evenly divisible by both 6 and 14 are also divisible by?"

Answer 1

2

any number divisible by 6 is divisible by prime factors of 6, 3 and 2

any number divisible by 14 is divisible by prime factors of 14: 7 and 2

the only common prime factor of both 6 and 14 is 2

BUT they may want to have you multiply all those prime factors together: 2x3x7 =42

only 21 divides it evenly given choices of 8, 12, 21 and 28