Here's how you add


Step 1We still have different denominators (bottom numbers), though, so we need to get a common denominator. This will make the bottom numbers match. Multiply the denominators together first. Now, multiply each numerator by the other term's denominator. Now we multiply 7 by 12, and get 84, then we multiply 9 by 12 and get 108. Now for the second term. You multiply 5 by 9, and get 45, then multiply 9 by 12 and get 108. This gives us a new problem that looks like so:


Step 2Since our denominators match, we can add the numerators. 84 + 45 = 129 That gives us an answer of


Step 3Can this fraction be reduced? First, we attempt to divide it by 2... Nope! So now we try the next greatest prime number, 3... Are both the numerator and the denominator evenly divisible by 3? Yes! So we reduce it:
Let's try dividing by that again... Nope! So now we try the next greatest prime number, 5... Nope! So now we try the next greatest prime number, 7... Nope! So now we try the next greatest prime number, 11... Nope! So now we try the next greatest prime number, 13... Nope! So now we try the next greatest prime number, 17... Nope! So now we try the next greatest prime number, 19... Nope! So now we try the next greatest prime number, 23... Nope! So now we try the next greatest prime number, 29... Nope! So now we try the next greatest prime number, 31... Nope! So now we try the next greatest prime number, 37... No good. 37 is larger than 36. So we're done reducing. There you have it! Here's the final answer to 7/9 + 5/12
