math help

What is 9/34 + 7/12?

What is 9/34 + 7/12?

This is how to add

9
34
+
7
12

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 9 by 12, and get 108, then we multiply 34 by 12 and get 408.

9/34 times 12

Do the same for the second term. We multiply 7 by 34, and get 238, then multiply 34 by 12 and get 408.

7/12 times 34

The problem now has new fractions to add:

108
408
+
238
408

Step 2

Since our denominators match, we can add the numerators.

108 + 238 = 346

The sum we get is

346
408

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:

346
408
÷ 2 =
173
204

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...

No good. So next you try the next prime number, which is 7...

No good. So next you try the next prime number, which is 11...

No good. So next you try the next prime number, which is 13...

No good. So next you try the next prime number, which is 17...

No good. So next you try the next prime number, which is 19...

No good. So next you try the next prime number, which is 23...

No good. So next you try the next prime number, which is 29...

No good. So next you try the next prime number, which is 31...

No good. So next you try the next prime number, which is 37...

No good. So next you try the next prime number, which is 41...

No good. So next you try the next prime number, which is 43...

No good. So next you try the next prime number, which is 47...

No good. So next you try the next prime number, which is 53...

No good. So next you try the next prime number, which is 59...

No good. So next you try the next prime number, which is 61...

No good. So next you try the next prime number, which is 67...

No good. So next you try the next prime number, which is 71...

No good. So next you try the next prime number, which is 73...

No good. So next you try the next prime number, which is 79...

No good. So next you try the next prime number, which is 83...

No good. So next you try the next prime number, which is 89...

No good. So next you try the next prime number, which is 97...

No good. So next you try the next prime number, which is 101...

No good. So next you try the next prime number, which is 103...

No good. So next you try the next prime number, which is 107...

No good. So next you try the next prime number, which is 109...

No good. So next you try the next prime number, which is 113...

No good. So next you try the next prime number, which is 127...

No good. So next you try the next prime number, which is 131...

No good. So next you try the next prime number, which is 137...

No good. So next you try the next prime number, which is 139...

No good. So next you try the next prime number, which is 149...

No good. So next you try the next prime number, which is 151...

No good. So next you try the next prime number, which is 157...

No good. So next you try the next prime number, which is 163...

No good. So next you try the next prime number, which is 167...

No good. So next you try the next prime number, which is 173...

No good. So next you try the next prime number, which is 179...

No good. 179 is larger than 173. So we're done reducing.

And we're done! Here's the final answer to 9/34 + 7/12

9
34
+
7
12
=
173
204
© 2014 Randy Tayler