math help

What is 36/4 + 7/9?

What is 36/4 + 7/9?

Here's how to add

36
4
+
7
9

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 36 by 9, and get 324, then we multiply 4 by 9 and get 36.

36/4 times 9

Do the same for the second term. We multiply 7 by 4, and get 28, then multiply 4 by 9 and get 36.

7/9 times 4

So now our fractions look like this:

324
36
+
28
36

Step 2

Since our denominators match, we can add the numerators.

324 + 28 = 352

So the answer is:

352
36

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:

352
36
÷ 2 =
176
18

So far so good... let's try to divide by that number again.

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

176
18
÷ 2 =
88
9

So far so good... let's try to divide by that number again.

No good. So next you try the next prime number, which is 3...

No good. So next you try the next prime number, which is 5...

No good. So next you try the next prime number, which is 7...

No good. So next you try the next prime number, which is 11...

No good. 11 is larger than 9. So we're done reducing.

And we're done! Here's the final answer to 36/4 + 7/9

36
4
+
7
9
=
88
9
© 2014 Randy Tayler