math help

What is 24/12 + 5/7?

What is 24/12 + 5/7?

This is how to add

24
12
+
5
7

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 24 by 7, and get 168, then we multiply 12 by 7 and get 84.

24/12 times 7

Do the same for the second term. We multiply 5 by 12, and get 60, then multiply 12 by 7 and get 84.

5/7 times 12

So now our fractions look like this:

168
84
+
60
84

Step 2

Since our denominators match, we can add the numerators.

168 + 60 = 228

So the answer is:

228
84

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...

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

228
84
÷ 2 =
114
42

Let's try dividing by that again...

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

114
42
÷ 2 =
57
21

Let's try dividing by that again...

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:

57
21
÷ 3 =
19
7

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...

No good. 11 is larger than 7. So we're done reducing.

There you have it! Here's the final answer to 24/12 + 5/7

24
12
+
5
7
=
19
7
© 2014 Randy Tayler