If you are dividing the fractions, reverse the positions of the numerator and denominator in the second fraction. For example, in the problem 3/5 divided by 2/5, flip the second fraction to 5/2. If you are multiplying the fractions, just skip to Step 2.
Multiply the numerators of the fractions and write the result as the numerator in the answer. For example, when multiplying 3/5 times 5/2, multiply 3 times 5 to get 15, which is the numerator in your answer.
Multiply the denominators in the fractions and write the result as the denominator in the answer. In this case, multiply 5 times 2 to find that the denominator is 10.
Write the answer as a fraction. For example, with a numerator of 15 and denominator of 10, it is 15/10.
Simplify the fraction, if possible, by factoring the same number out of the numerator and denominator. In the case of 15/10, factor 5 out of each of them to simplify it to 3/2 or 1 1/2.
Look at the denominators of the fractions you are adding or subtracting. If they are the same, skip to Step 3.
Multiply the top and bottom of the first fraction by the denominator of the second fraction. For example, if your fractions are 1/3 and 1/4, multiply 1/3 by 4/4 to get 4/12. Do the same with the second fraction, multiplying 1/4 by 3/3 to get 3/12. Now your fractions are 4/12 and 3/12.
Add or subtract the numerators of the fractions as indicated in the problem. For example, if the problem asks for 4/12 plus 3/12, add 4 plus 3 to get 7.
Write the result as the numerator of your answer and write the denominator of the fractions as the denominator of your answer. In this case, you would have 7/12.
Simplify the fraction as described in Step 5 of the first section. In this case, 7/12 is as simple as it gets.