math help

What is 8/13 + 7/12?

What is 8/13 + 7/12?

Here's how you add

8
13
+
7
12

Step 1

We can't add two fractions with different denominators (the bottom number). So you need to get a common denominator - both bottom numbers need to match. To do this, you'll multiply the denominators times each other... but the numerators have to change, too. They get multiplied by the other term's denominator.

So we multiply 8 by 12, and get 96, then we multiply 13 by 12 and get 156.

8/13 times 12

Do the same for the second term. We multiply 7 by 13, and get 91, then multiply 13 by 12 and get 156.

7/12 times 13

So now our fractions look like this:

96
156
+
91
156

Step 2

Since our denominators match, we can add the numerators.

96 + 91 = 187

So the answer is:

187
156

Step 3

Last of all, we need to simplify the fraction, if possible. Can it be reduced to a simpler fraction?

To find out, we try dividing it by 2...

Nope. Try the next prime number, 3...

Nope. Try the next prime number, 5...

Nope. Try the next prime number, 7...

Nope. Try the next prime number, 11...

Nope. Try the next prime number, 13...

Nope. Try the next prime number, 17...

Nope. Try the next prime number, 19...

Nope. Try the next prime number, 23...

Nope. Try the next prime number, 29...

Nope. Try the next prime number, 31...

Nope. Try the next prime number, 37...

Nope. Try the next prime number, 41...

Nope. Try the next prime number, 43...

Nope. Try the next prime number, 47...

Nope. Try the next prime number, 53...

Nope. Try the next prime number, 59...

Nope. Try the next prime number, 61...

Nope. Try the next prime number, 67...

Nope. Try the next prime number, 71...

Nope. Try the next prime number, 73...

Nope. Try the next prime number, 79...

Nope. Try the next prime number, 83...

Nope. Try the next prime number, 89...

Nope. Try the next prime number, 97...

Nope. Try the next prime number, 101...

Nope. Try the next prime number, 103...

Nope. Try the next prime number, 107...

Nope. Try the next prime number, 109...

Nope. Try the next prime number, 113...

Nope. Try the next prime number, 127...

Nope. Try the next prime number, 131...

Nope. Try the next prime number, 137...

Nope. Try the next prime number, 139...

Nope. Try the next prime number, 149...

Nope. Try the next prime number, 151...

Nope. Try the next prime number, 157...

No good. 157 is larger than 156. So we're done reducing.

Congratulations! Here's your final answer to 8/13 + 7/12

8
13
+
7
12
=
187
156
© 2014 Randy Tayler