How do you simplify number fractions

divide by a common multiple.

For example if the fraction is 50/100, what you have to do is find a number that fits into both 50 and 100. There are a lot of numbers but you have to try and find the highest number, so in this case it would be 50. So 50/50 is 1, and 100/50 would be 2, so the answer is 1/2.