math help

What is 31/12 + 1/8?

What is 31/12 + 1/8?

This is how we add

31
12
+
1
8

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 31 by 8, and get 248, then we multiply 12 by 8 and get 96.

31/12 times 8

Do the same for the second term. We multiply 1 by 12, and get 12, then multiply 12 by 8 and get 96.

1/8 times 12

So now our fractions look like this:

248
96
+
12
96

Step 2

Since our denominators match, we can add the numerators.

248 + 12 = 260

Now we have an answer.

260
96

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...

Are both the numerator and the denominator evenly divisible by 2? Yes! So we reduce it:

260
96
÷ 2 =
130
48

Now, try the same number again.

Are both the numerator and the denominator evenly divisible by 2? Yes! So we reduce it:

130
48
÷ 2 =
65
24

Now, try the same number again.

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...

No good. 29 is larger than 24. So we're done reducing.

Congratulations! Here's your final answer to 31/12 + 1/8

31
12
+
1
8
=
65
24
© 2014 Randy Tayler