math help

What is 20/64 + 2/9?

What is 20/64 + 2/9?

Here's how we add

20
64
+
2
9

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 9, and get 180, then we multiply 64 by 9 and get 576.

20/64 times 9

Now for the second term. You multiply 2 by 64, and get 128, then multiply 64 by 9 and get 576.

2/9 times 64

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

180
576
+
128
576

Step 2

Since our denominators match, we can add the numerators.

180 + 128 = 308

That gives us the sum, which is

308
576

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:

308
576
÷ 2 =
154
288

So far so good... let's try to divide by that number again.

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

154
288
÷ 2 =
77
144

So far so good... let's try to divide by that number again.

No good. So next you try the next prime number, which is 3...

No good. So next you try the next prime number, which is 5...

No good. So next you try the next prime number, which is 7...

No good. So next you try the next prime number, which is 11...

No good. So next you try the next prime number, which is 13...

No good. So next you try the next prime number, which is 17...

No good. So next you try the next prime number, which is 19...

No good. So next you try the next prime number, which is 23...

No good. So next you try the next prime number, which is 29...

No good. So next you try the next prime number, which is 31...

No good. So next you try the next prime number, which is 37...

No good. So next you try the next prime number, which is 41...

No good. So next you try the next prime number, which is 43...

No good. So next you try the next prime number, which is 47...

No good. So next you try the next prime number, which is 53...

No good. So next you try the next prime number, which is 59...

No good. So next you try the next prime number, which is 61...

No good. So next you try the next prime number, which is 67...

No good. So next you try the next prime number, which is 71...

No good. So next you try the next prime number, which is 73...

No good. So next you try the next prime number, which is 79...

No good. 79 is larger than 77. So we're done reducing.

And we're done! Here's the final answer to 20/64 + 2/9

20
64
+
2
9
=
77
144
© 2014 Randy Tayler