math help

What is 53/9 - 2/12?

What is 53/9 - 2/12?

Here's how to subtract 2/12 from 53/9:

53
9
2
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 53 by 12, and get 636.

Then we multiply 2 by 9, and get 18.

Next we give both terms new denominators -- 9 × 12 = 108.

So now our fractions look like this:

636
108
18
108

Step 2

Since our denominators match, we can subtract the numerators.

636 − 18 = 618

So the answer is:

618
108

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:

618
108
÷ 2 =
309
54

Let's try dividing by 2 again...

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:

309
54
÷ 3 =
103
18

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...

No good. 19 is larger than 18. So we're done reducing.

There you have it! The final answer is:
53
9
2
12
=
103
18