math help

What is 20/64 + 6/7?

What is 20/64 + 6/7?

This is how to add

20
64
+
6
7

Step 1

We still have different denominators (bottom numbers), though, so we need to get a common denominator. This will make the bottom numbers match. Multiply the denominators together first. Now, multiply each numerator by the other term's denominator.

Now we multiply 20 by 7, and get 140, then we multiply 64 by 7 and get 448.

20/64 times 7

Now for the second term. You multiply 6 by 64, and get 384, then multiply 64 by 7 and get 448.

6/7 times 64

This gives us a new problem that looks like so:

140
448
+
384
448

Step 2

Since our denominators match, we can add the numerators.

140 + 384 = 524

That gives us an answer of

524
448

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:

524
448
÷ 2 =
262
224

Now, try the same number again.

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

262
224
÷ 2 =
131
112

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...

Nope. Try the next prime number, 61...

Nope. Try the next prime number, 67...

Nope. Try the next prime number, 71...

Nope. Try the next prime number, 73...

Nope. Try the next prime number, 79...

Nope. Try the next prime number, 83...

Nope. Try the next prime number, 89...

Nope. Try the next prime number, 97...

Nope. Try the next prime number, 101...

Nope. Try the next prime number, 103...

Nope. Try the next prime number, 107...

Nope. Try the next prime number, 109...

Nope. Try the next prime number, 113...

No good. 113 is larger than 112. So we're done reducing.

Congratulations! Here's your final answer to 20/64 + 6/7

20
64
+
6
7
=
131
112
© 2014 Randy Tayler