math help

What is 10/11 + 3/9?

What is 10/11 + 3/9?

Here's how you add

10
11
+
3
9

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 10 by 9, and get 90, then we multiply 11 by 9 and get 99.

10/11 times 9

Now for the second term. You multiply 3 by 11, and get 33, then multiply 11 by 9 and get 99.

3/9 times 11

This gives us a new problem that looks like so:

90
99
+
33
99

Step 2

Since our denominators match, we can add the numerators.

90 + 33 = 123

That gives us an answer of

123
99

Step 3

Can this fraction be reduced?

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

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

Are both the numerator and the denominator evenly divisible by 3? Yes! So we reduce it:

123
99
÷ 3 =
41
33

Let's try dividing by that again...

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 33. So we're done reducing.

There you have it! Here's the final answer to 10/11 + 3/9

10
11
+
3
9
=
41
33
© 2014 Randy Tayler