math help

What is 20/64 + 2/5?

What is 20/64 + 2/5?

Here's how to add

20
64
+
2
5

Step 1

Can you add yet? Nope! The denominators don't match. We need a common denominator. So next we take both denominators and multiply them. Next, take each numerator and multiply it by the denominator of the other term.

So, we multiply 20 by 5, and get 100, then we multiply 64 by 5 and get 320.

20/64 times 5

Now for the second term. You multiply 2 by 64, and get 128, then multiply 64 by 5 and get 320.

2/5 times 64

We now have a new problem, that looks like this:

100
320
+
128
320

Step 2

Since our denominators match, we can add the numerators.

100 + 128 = 228

Answer:

228
320

Step 3

Now, do we need to simplify this fraction?

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

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

228
320
÷ 2 =
114
160

Now, try the same number again.

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

114
160
÷ 2 =
57
80

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...

Nope. Try the next prime number, 19...

Nope. Try the next prime number, 23...

Nope. Try the next prime number, 29...

Nope. Try the next prime number, 31...

Nope. Try the next prime number, 37...

Nope. Try the next prime number, 41...

Nope. Try the next prime number, 43...

Nope. Try the next prime number, 47...

Nope. Try the next prime number, 53...

Nope. Try the next prime number, 59...

No good. 59 is larger than 57. So we're done reducing.

Congratulations! Here's your final answer to 20/64 + 2/5

20
64
+
2
5
=
57
80
© 2014 Randy Tayler