Question

What is the common denominator of `2/3, 3/4,` and `5/8`?

Answer 1

The common denominator is `24`.

Explanation:

We are only interested in the numbers on the bottom - Denominators.

The method in use here is to multiply the odd denominator in the list by the largest even denominator, then check to see if the remaining denominator will divide into it. Then divide the result by two to see if there is a smaller common denominator that will work. There are other methods.

For this example, `2/3, 3/4, 5/8,` multiply the odd `3` by the larger, even `8` to get `24`, and then divide by `2` to get `12`.

We can see that all three numbers will divide into `24`, but the `8` will not divide into `12`, so `24` is our answer.

Note that if there are more odd numbers in the list than even, you would multiply the even denominator in the list by the largest odd denominator. In some cases you will need to multiply all three denominators.