math help

What is 20/64 + 5/10?

What is 20/64 + 5/10?

Let's add

20
64
+
5
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 64 by 10 and get 640.

20/64 times 10

Now for the second term. You multiply 5 by 64, and get 320, then multiply 64 by 10 and get 640.

5/10 times 64

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

200
640
+
320
640

Step 2

Since our denominators match, we can add the numerators.

200 + 320 = 520

Answer:

520
640

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:

520
640
÷ 2 =
260
320

Let's try dividing by that again...

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

260
320
÷ 2 =
130
160

Let's try dividing by that again...

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

130
160
÷ 2 =
65
80

Let's try dividing by that again...

Nope! So now we try the next greatest prime number, 3...

Nope! So now we try the next greatest prime number, 5...

Are both the numerator and the denominator evenly divisible by 5? Yes! So we reduce it:

65
80
÷ 5 =
13
16

Let's try dividing by that again...

Nope! So now we try the next greatest prime number, 7...

Nope! So now we try the next greatest prime number, 11...

Nope! So now we try the next greatest prime number, 13...

Nope! So now we try the next greatest prime number, 17...

No good. 17 is larger than 13. So we're done reducing.

There you have it! Here's the final answer to 20/64 + 5/10

20
64
+
5
10
=
13
16
© 2014 Randy Tayler