math help

What is 20/17 + 8/10?

What is 20/17 + 8/10?

This is how to add

20
17
+
8
10

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 10, and get 200, then we multiply 17 by 10 and get 170.

20/17 times 10

Now for the second term. You multiply 8 by 17, and get 136, then multiply 17 by 10 and get 170.

8/10 times 17

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

200
170
+
136
170

Step 2

Since our denominators match, we can add the numerators.

200 + 136 = 336

That gives us the sum, which is

336
170

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:

336
170
÷ 2 =
168
85

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...

No good. 89 is larger than 85. So we're done reducing.

Congratulations! Here's your final answer to 20/17 + 8/10

20
17
+
8
10
=
168
85
© 2014 Randy Tayler