math help

What is 100/72 + 5/12?

What is 100/72 + 5/12?

Here's how to add

100
72
+
5
12

Step 1

Now we need to make our denominators match.

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

Multiply 5 by 6, and get 30, then we multiply 12 by 6 and get 72.

5/12 times 6

This gives us a new problem that looks like so:

100
72
+
30
72

Step 2

Since our denominators match, we can add the numerators.

100 + 30 = 130

So what's the answer so far?

130
72

Step 3

Can this fraction be reduced?

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

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

130
72
÷ 2 =
65
36

Let's try dividing by that again...

Nope! So now we try the next greatest prime number, 3...

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 100/72 + 5/12

100
72
+
5
12
=
65
36
© 2014 Randy Tayler