math help

What is 7/10 - 4/8?

What is 7/10 - 4/8?

Here's how to subtract 4/8 from 7/10:

7
10
4
8

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 7 by 8, and get 56.

Then we multiply 4 by 10, and get 40.

Next we give both terms new denominators -- 10 × 8 = 80.

So now our fractions look like this:

56
80
40
80

Step 2

Since our denominators match, we can subtract the numerators.

56 − 40 = 16

So the answer is:

16
80

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:

16
80
÷ 2 =
8
40

Let's try dividing by 2 again...

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

8
40
÷ 2 =
4
20

Let's try dividing by 2 again...

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

4
20
÷ 2 =
2
10

Let's try dividing by 2 again...

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

2
10
÷ 2 =
1
5

Let's try dividing by 2 again...

No good. 2 is larger than 1. So we're done reducing.

There you have it! The final answer is:
7
10
4
8
=
1
5