math help

What is 20/17 + 5/7?

What is 20/17 + 5/7?

Here's how to add

20
17
+
5
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 17 by 7 and get 119.

20/17 times 7

Now for the second term. You multiply 5 by 17, and get 85, then multiply 17 by 7 and get 119.

5/7 times 17

This gives us a new problem that looks like so:

140
119
+
85
119

Step 2

Since our denominators match, we can add the numerators.

140 + 85 = 225

That gives us an answer of

225
119

Step 3

Can this fraction be reduced?

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

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...

Nope. Try the next prime number, 127...

No good. 127 is larger than 119. So we're done reducing.

Congratulations! Here's your final answer to 20/17 + 5/7

20
17
+
5
7
=
225
119
© 2014 Randy Tayler