math help

What is 64/17 + 3/12?

What is 64/17 + 3/12?

Here's how you add

64
17
+
3
12

Step 1

We can't add two fractions with different denominators (the bottom number). So you need to get a common denominator - both bottom numbers need to match. To do this, you'll multiply the denominators times each other... but the numerators have to change, too. They get multiplied by the other term's denominator.

So we multiply 64 by 12, and get 768, then we multiply 17 by 12 and get 204.

64/17 times 12

Do the same for the second term. We multiply 3 by 17, and get 51, then multiply 17 by 12 and get 204.

3/12 times 17

So now our fractions look like this:

768
204
+
51
204

Step 2

Since our denominators match, we can add the numerators.

768 + 51 = 819

So the answer is:

819
204

Step 3

Last of all, we need to simplify the fraction, if possible. Can it be reduced to a simpler fraction?

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

Nope! So now we try the next greatest prime number, 3...

Are both the numerator and the denominator evenly divisible by 3? Yes! So we reduce it:

819
204
÷ 3 =
273
68

Let's try dividing by that again...

Nope! So now we try the next greatest prime number, 5...

Nope! So now we try the next greatest prime number, 7...

Nope! So now we try the next greatest prime number, 11...

Nope! So now we try the next greatest prime number, 13...

Nope! So now we try the next greatest prime number, 17...

Nope! So now we try the next greatest prime number, 19...

Nope! So now we try the next greatest prime number, 23...

Nope! So now we try the next greatest prime number, 29...

Nope! So now we try the next greatest prime number, 31...

Nope! So now we try the next greatest prime number, 37...

Nope! So now we try the next greatest prime number, 41...

Nope! So now we try the next greatest prime number, 43...

Nope! So now we try the next greatest prime number, 47...

Nope! So now we try the next greatest prime number, 53...

Nope! So now we try the next greatest prime number, 59...

Nope! So now we try the next greatest prime number, 61...

Nope! So now we try the next greatest prime number, 67...

Nope! So now we try the next greatest prime number, 71...

No good. 71 is larger than 68. So we're done reducing.

There you have it! Here's the final answer to 64/17 + 3/12

64
17
+
3
12
=
273
68
© 2014 Randy Tayler