Which number is a composite number? 1,2,7,9

24

Step by Step Reasoning:

The problem is basic 6th grade math, you must find the lcm for the problem

8 to 12. My method I use is called the "Ladder" method.

 8 to 12                              What goes into both 8 and 12? 4!

4|                           How many times does 4 go into 8? 2!

 2     3                               How many times does 4 go into 12? 3!

                                                              Multiply those numbers to get 24

this also works with gcf to... which is going to always the first number you place down, which in this case it is 4.