This is how you add


Step 1Can you add yet? Nope! The denominators don't match. We need a common denominator. So next we take both denominators and multiply them. Next, take each numerator and multiply it by the denominator of the other term. So, we multiply 3 by 9, and get 27, then we multiply 7 by 9 and get 63. Now for the second term. You multiply 4 by 7, and get 28, then multiply 7 by 9 and get 63. We now have a new problem, that looks like this:


Step 2Since our denominators match, we can add the numerators. 27 + 28 = 55 That gives us the sum, which is


Step 3Now, do we need to simplify this fraction? First, we attempt to divide it by 2... No good. So next you try the next prime number, which is 3... No good. So next you try the next prime number, which is 5... No good. So next you try the next prime number, which is 7... No good. So next you try the next prime number, which is 11... No good. So next you try the next prime number, which is 13... No good. So next you try the next prime number, which is 17... No good. So next you try the next prime number, which is 19... No good. So next you try the next prime number, which is 23... No good. So next you try the next prime number, which is 29... No good. So next you try the next prime number, which is 31... No good. So next you try the next prime number, which is 37... No good. So next you try the next prime number, which is 41... No good. So next you try the next prime number, which is 43... No good. So next you try the next prime number, which is 47... No good. So next you try the next prime number, which is 53... No good. So next you try the next prime number, which is 59... No good. 59 is larger than 55. So we're done reducing. And we're done! Here's the final answer to 3/7 + 4/9
