math help

What is 31/12 + 5/7?

What is 31/12 + 5/7?

This is how to add

31
12
+
5
7

Step 1

Can 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 31 by 7, and get 217, then we multiply 12 by 7 and get 84.

31/12 times 7

Now for the second term. You multiply 5 by 12, and get 60, then multiply 12 by 7 and get 84.

5/7 times 12

We now have a new problem, that looks like this:

217
84
+
60
84

Step 2

Since our denominators match, we can add the numerators.

217 + 60 = 277

That gives us the sum, which is

277
84

Step 3

Now, do we need to simplify this fraction?

First, we attempt to divide 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...

No good. 89 is larger than 84. So we're done reducing.

Congratulations! Here's your final answer to 31/12 + 5/7

31
12
+
5
7
=
277
84
© 2014 Randy Tayler