This week we learned about Prime Factoring. Prime Factoring is taking a number and finding its Prime Factors. For example the prime factorization of 12 is 2² x 3 or rewritten is 2 x 2 x 3.

In order to find a number’s prime factors, you need to follow divisibility rules.

2 – ends in an even number

3 – add all digits. If the sum is divisible by 3, the number is divisible by 3

4 – the last 2 digits of a number are divisible by 4. Can be cut in half twice

5 – ends in a 5 or 0

6 – if both 2 and 3 apply

7 – there is no rule

8 – can be cut in half 3 times

9 – digit sum is divisible by 9

10 – ends in a 0

Here is a guide to factorization:

1. Check if your number is divisible by 2 (if there is any larger number that is divisible do that)
   1. If yes move on to the next step
   2. If no skip to step 4
2. Divide
3. Check if your quotient is still divisible by 2
   1. If yes, go back to step 2
   2. If no, move on the next step
4. Repeat step 1-3 for the other factorization numbers