Question

Write 42 as a product of three primes

Answer 1

Answer:   42 = 2*3*7

Explanation:

Here is list of the first few primes = {2, 3, 5, 7, 11}

Divide 42 over the smallest prime 2 and we get

42/2 = 21

This shows that 2 is a factor (since we get a whole number result).

We don't have another factor of 2 because 21/2 = 10.5 isn't a whole number. But 3 is a factor because 21/3 = 7

Ultimately the numbers 2, 3 and 7 are factors of 42. They are the only prime factors and there's only one copy of each.

42 = 2*3*7

Check out the diagram below. It shows two different ways to generate a factor tree for the number 42.