math help

What is 4/40 + 2/11?

What is 4/40 + 2/11?

Let's add

4
40
+
2
11

Step 1

We still have different denominators (bottom numbers), though, so we need to get a common denominator. This will make the bottom numbers match. Multiply the denominators together first. Now, multiply each numerator by the other term's denominator.

Now we multiply 4 by 11, and get 44, then we multiply 40 by 11 and get 440.

4/40 times 11

Now for the second term. You multiply 2 by 40, and get 80, then multiply 40 by 11 and get 440.

2/11 times 40

This gives us a new problem that looks like so:

44
440
+
80
440

Step 2

Since our denominators match, we can add the numerators.

44 + 80 = 124

That gives us an answer of

124
440

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:

124
440
÷ 2 =
62
220

Let's try dividing by that again...

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

62
220
÷ 2 =
31
110

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 31. So we're done reducing.

There you have it! Here's the final answer to 4/40 + 2/11

4
40
+
2
11
=
31
110
© 2014 Randy Tayler