math help

What is 24/5 - 3/12?

What is 24/5 - 3/12?

Here's how to subtract 3/12 from 24/5:

24
5
3
12

Step 1

We can't subtract two fractions with different denominators. So you need to get a common denominator. 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 3 by 5, and get 15.

Next we give both terms new denominators -- 5 × 12 = 60.

So now our fractions look like this:

288
60
15
60

Step 2

Since our denominators match, we can subtract the numerators.

288 − 15 = 273

So the answer is:

273
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...

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:

273
60
÷ 3 =
91
20

Let's try dividing by 3 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...

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

There you have it! The final answer is:
24
5
3
12
=
91
20