math help

What is 5/100 + 6/8?

What is 5/100 + 6/8?

Here's how to add

5
100
+
6
8

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 5 by 8, and get 40, then we multiply 100 by 8 and get 800.

5/100 times 8

Now for the second term. You multiply 6 by 100, and get 600, then multiply 100 by 8 and get 800.

6/8 times 100

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

40
800
+
600
800

Step 2

Since our denominators match, we can add the numerators.

40 + 600 = 640

That gives us the sum, which is

640
800

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:

640
800
÷ 2 =
320
400

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:

320
400
÷ 2 =
160
200

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:

160
200
÷ 2 =
80
100

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:

80
100
÷ 2 =
40
50

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:

40
50
÷ 2 =
20
25

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...

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

20
25
÷ 5 =
4
5

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

No good. 5 is larger than 4. So we're done reducing.

And we're done! Here's the final answer to 5/100 + 6/8

5
100
+
6
8
=
4
5
© 2014 Randy Tayler