math help

What is 57/7 + 4/8?

What is 57/7 + 4/8?

This is how to add

57
7
+
4
8

Step 1

We can't add two fractions with different denominators (the bottom number). So you need to get a common denominator - both bottom numbers need to match. 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 57 by 8, and get 456, then we multiply 7 by 8 and get 56.

57/7 times 8

Do the same for the second term. We multiply 4 by 7, and get 28, then multiply 7 by 8 and get 56.

4/8 times 7

So now our fractions look like this:

456
56
+
28
56

Step 2

Since our denominators match, we can add the numerators.

456 + 28 = 484

Now we have an answer.

484
56

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:

484
56
÷ 2 =
242
28

Now, try the same number again.

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

242
28
÷ 2 =
121
14

Now, try the same number again.

Nope. Try the next prime number, 3...

Nope. Try the next prime number, 5...

Nope. Try the next prime number, 7...

Nope. Try the next prime number, 11...

Nope. Try the next prime number, 13...

Nope. Try the next prime number, 17...

No good. 17 is larger than 14. So we're done reducing.

Congratulations! Here's your final answer to 57/7 + 4/8

57
7
+
4
8
=
121
14
© 2014 Randy Tayler