Question

What is the least common denominator of 1/5 and 1/8 ?

Answer 1

`40`

Explanation:

The least common denominator of two fractions is the lowest possible number that is a multiple of both denominators.

You have to find the least common multiple of
`5` and `8`

The easiest way to do this is start listing the multiples of each of the numbers until you have two that match. These are the least common denominators.

Multiples of 5: `5,10,15,20,25,30,35,color(red)40`
Multiples of 8: `8,16,24,32,color(red)40`

So the lowest number that they both share is `color(red)40`. This is the least common denominator.

Now we'll change the fractions so that they have `40` as their denominator. Remember we need to multiply the top and bottom by the same number so that their value stays the same:

`1/5 xx 8/8 = 8/40`

`1/8 xx 5/5 = 5/40`