math help

What is 4/40 + 9/11?

What is 4/40 + 9/11?

Let's add

4
40
+
9
11

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

4/40 times 11

Do the same for the second term. We multiply 9 by 40, and get 360, then multiply 40 by 11 and get 440.

9/11 times 40

So now our fractions look like this:

44
440
+
360
440

Step 2

Since our denominators match, we can add the numerators.

44 + 360 = 404

So the answer is:

404
440

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:

404
440
÷ 2 =
202
220

Now, try the same number again.

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

202
220
÷ 2 =
101
110

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...

Nope. Try the next prime number, 41...

Nope. Try the next prime number, 43...

Nope. Try the next prime number, 47...

Nope. Try the next prime number, 53...

Nope. Try the next prime number, 59...

Nope. Try the next prime number, 61...

Nope. Try the next prime number, 67...

Nope. Try the next prime number, 71...

Nope. Try the next prime number, 73...

Nope. Try the next prime number, 79...

Nope. Try the next prime number, 83...

Nope. Try the next prime number, 89...

Nope. Try the next prime number, 97...

Nope. Try the next prime number, 101...

Nope. Try the next prime number, 103...

No good. 103 is larger than 101. So we're done reducing.

Congratulations! Here's your final answer to 4/40 + 9/11

4
40
+
9
11
=
101
110
© 2014 Randy Tayler