math help

What is 9/100 + 4/5?

What is 9/100 + 4/5?

This is how to add

9
100
+
4
5

Step 1

Our denominators (bottom numbers) don't match, so we can't add yet.

Since 5 is evenly divided by 100, we can multiply just one term to get a common denominator.

Multiply 4 by 20, and get 80, then we multiply 5 by 20 and get 100.

4/5 times 20

The problem now has new fractions to add:

9
100
+
80
100

Step 2

Since our denominators match, we can add the numerators.

9 + 80 = 89

The sum we get is

89
100

Step 3

The last step is to reduce the fraction if we can.

To find out, we try dividing it by 2...

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...

Nope. Try the next prime number, 97...

No good. 97 is larger than 89. So we're done reducing.

Congratulations! Here's your final answer to 9/100 + 4/5

9
100
+
4
5
=
89
100
© 2014 Randy Tayler