math help

What is 100/72 + 3/12?

What is 100/72 + 3/12?

Here's how you add

100
72
+
3
12

Step 1

Our denominators (bottom numbers) don't match, so we can't add yet.

72 goes into 12 evenly, so we only need to multiply one term to get a common denominator.

Multiply 3 by 6, and get 18, then we multiply 12 by 6 and get 72.

3/12 times 6

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

100
72
+
18
72

Step 2

Since our denominators match, we can add the numerators.

100 + 18 = 118

Answer:

118
72

Step 3

Now, do we need to simplify this fraction?

First, we attempt to divide it by 2...

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

118
72
÷ 2 =
59
36

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...

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

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

No good. 37 is larger than 36. So we're done reducing.

Congratulations! Here's your final answer to 100/72 + 3/12

100
72
+
3
12
=
59
36
© 2014 Randy Tayler