math help

What is 4/40 + 3/8?

What is 4/40 + 3/8?

This is how to add

4
40
+
3
8

Step 1

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

40 goes into 8 evenly, so we only need to multiply one term to get a common denominator.

Multiply 3 by 5, and get 15, then we multiply 8 by 5 and get 40.

3/8 times 5

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

4
40
+
15
40

Step 2

Since our denominators match, we can add the numerators.

4 + 15 = 19

That gives us the sum, which is

19
40

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...

No good. 23 is larger than 19. So we're done reducing.

Congratulations! Here's your final answer to 4/40 + 3/8

4
40
+
3
8
=
19
40
© 2014 Randy Tayler