math help

What is 2/12 + 9/11?

What is 2/12 + 9/11?

This is how to add

2
12
+
9
11

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 2 by 11, and get 22, then we multiply 12 by 11 and get 132.

2/12 times 11

Do the same for the second term. We multiply 9 by 12, and get 108, then multiply 12 by 11 and get 132.

9/11 times 12

The problem now has new fractions to add:

22
132
+
108
132

Step 2

Since our denominators match, we can add the numerators.

22 + 108 = 130

This yields the answer

130
132

Step 3

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

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

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

130
132
÷ 2 =
65
66

Now, try the same number again.

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...

No good. 67 is larger than 65. So we're done reducing.

Congratulations! Here's your final answer to 2/12 + 9/11

2
12
+
9
11
=
65
66
© 2014 Randy Tayler