When simplifying a fraction do you find the highest number that goes into both numerator/denominator or the lowest number?
The highest common factor.
Let's take the example
To simplify, you want to find the highest common factor of the numerator and the denominator, that is the largest number which goes into both numbers.
We can see by looking at the numbers
Finally, we can divide both the numerator and the denominator by this number,
This answer expands on the one provided before.
Consider the fraction
How can we do that? By using a creative form of the number 1.
Recall that anything divided by itself equals 1:
And so I can multiply the fraction
and the result of those multiplications is:
We can go the other way as well. By factoring out, from the numerator and denominator, equal values, we get back to the lowest terms fraction. For instance, going from