math help

What is 20/64 + 5/8?

What is 20/64 + 5/8?

This is how to add

20
64
+
5
8

Step 1

Our denominators (bottom numbers) don't match, so we can't add yet.

64 goes into 8 evenly, so we only need to multiply one term to get a common denominator.

Multiply 5 by 8, and get 40, then we multiply 8 by 8 and get 64.

5/8 times 8

This gives us a new problem that looks like so:

20
64
+
40
64

Step 2

Since our denominators match, we can add the numerators.

20 + 40 = 60

That gives us an answer of

60
64

Step 3

Can this fraction be reduced?

First, we attempt to divide it by 2...

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

60
64
÷ 2 =
30
32

Now, try the same number again.

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

30
32
÷ 2 =
15
16

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 15. So we're done reducing.

Congratulations! Here's your final answer to 20/64 + 5/8

20
64
+
5
8
=
15
16
© 2014 Randy Tayler