math help

What is 9/34 - 6/12?

What is 9/34 - 6/12?

Here's how to subtract 6/12 from 9/34:

9
34
6
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 9 by 12, and get 108.

Then we multiply 6 by 34, and get 204.

Next we give both terms new denominators -- 34 × 12 = 408.

So now our fractions look like this:

108
408
204
408

Step 2

Since our denominators match, we can subtract the numerators.

108 − 204 = -96

So the answer is:

-96
408

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:

-96
408
÷ 2 =
-48
204

Let's try dividing by 2 again...

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

-48
204
÷ 2 =
-24
102

Let's try dividing by 2 again...

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

-24
102
÷ 2 =
-12
51

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:

-12
51
÷ 3 =
-4
17

Let's try dividing by 3 again...

Nope! So now we try the next greatest prime number, 5...

No good. 5 is larger than -4. So we're done reducing.

There you have it! The final answer is:
9
34
6
12
=
4
17