math help

What is 21/11 + 5/9?

What is 21/11 + 5/9?

Here's how we add

21
11
+
5
9

Step 1

Of course, you can't add two fractions if the denominators (bottom numbers) don't match. To get a common denominator, multiply the denominators together. Then we fix the numerators by multiplying each one by their other term's denominator.

Now you multiply 21 by 9, and get 189, then we multiply 11 by 9 and get 99.

21/11 times 9

Do the same for the second term. We multiply 5 by 11, and get 55, then multiply 11 by 9 and get 99.

5/9 times 11

The problem now has new fractions to add:

189
99
+
55
99

Step 2

Since our denominators match, we can add the numerators.

189 + 55 = 244

The sum we get is

244
99

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...

Nope. Try the next prime number, 101...

No good. 101 is larger than 99. So we're done reducing.

Congratulations! Here's your final answer to 21/11 + 5/9

21
11
+
5
9
=
244
99
© 2014 Randy Tayler