math help

What is 24/5 + 3/12?

What is 24/5 + 3/12?

This is how you add

24
5
+
3
12

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 24 by 12, and get 288, then we multiply 5 by 12 and get 60.

24/5 times 12

Do the same for the second term. We multiply 3 by 5, and get 15, then multiply 5 by 12 and get 60.

3/12 times 5

So now our fractions look like this:

288
60
+
15
60

Step 2

Since our denominators match, we can add the numerators.

288 + 15 = 303

Now we have an answer.

303
60

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...

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

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

303
60
÷ 3 =
101
20

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 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. So next you try the next prime number, which is 13...

No good. So next you try the next prime number, which is 17...

No good. So next you try the next prime number, which is 19...

No good. So next you try the next prime number, which is 23...

No good. 23 is larger than 20. So we're done reducing.

And we're done! Here's the final answer to 24/5 + 3/12

24
5
+
3
12
=
101
20
© 2014 Randy Tayler