math help

What is 48/30 - 4/12?

What is 48/30 - 4/12?

Here's how to subtract 4/12 from 48/30:

48
30
4
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 48 by 12, and get 576.

Then we multiply 4 by 30, and get 120.

Next we give both terms new denominators -- 30 × 12 = 360.

So now our fractions look like this:

576
360
120
360

Step 2

Since our denominators match, we can subtract the numerators.

576 − 120 = 456

So the answer is:

456
360

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:

456
360
÷ 2 =
228
180

Let's try dividing by 2 again...

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

228
180
÷ 2 =
114
90

Let's try dividing by 2 again...

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

114
90
÷ 2 =
57
45

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:

57
45
÷ 3 =
19
15

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...

No good. 17 is larger than 15. So we're done reducing.

There you have it! The final answer is:
48
30
4
12
=
19
15