math help

What is 5/100 + 2/8?

What is 5/100 + 2/8?

This is how we add

5
100
+
2
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 2 by 100, and get 200, then multiply 100 by 8 and get 800.

2/8 times 100

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

40
800
+
200
800

Step 2

Since our denominators match, we can add the numerators.

40 + 200 = 240

Answer:

240
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:

240
800
÷ 2 =
120
400

Now, try the same number again.

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

120
400
÷ 2 =
60
200

Now, try the same number again.

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

60
200
÷ 2 =
30
100

Now, try the same number again.

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

30
100
÷ 2 =
15
50

Now, try the same number again.

Nope. Try the next prime number, 3...

Nope. Try the next prime number, 5...

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

15
50
÷ 5 =
3
10

Now, try the same number again.

No good. 5 is larger than 3. So we're done reducing.

Congratulations! Here's your final answer to 5/100 + 2/8

5
100
+
2
8
=
3
10
© 2014 Randy Tayler