math help

What is 100/50 + 8/12?

What is 100/50 + 8/12?

This is how you add

100
50
+
8
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 100 by 12, and get 1200, then we multiply 50 by 12 and get 600.

100/50 times 12

Do the same for the second term. We multiply 8 by 50, and get 400, then multiply 50 by 12 and get 600.

8/12 times 50

The problem now has new fractions to add:

1200
600
+
400
600

Step 2

Since our denominators match, we can add the numerators.

1200 + 400 = 1600

This yields the answer

1600
600

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:

1600
600
÷ 2 =
800
300

So far so good... let's try to divide by that number again.

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

800
300
÷ 2 =
400
150

So far so good... let's try to divide by that number again.

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

400
150
÷ 2 =
200
75

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...

Are both the numerator and the denominator evenly divisible by 5? Yes! So we reduce it:

200
75
÷ 5 =
40
15

So far so good... let's try to divide by that number again.

Are both the numerator and the denominator evenly divisible by 5? Yes! So we reduce it:

40
15
÷ 5 =
8
3

So far so good... let's try to divide by that number again.

No good. 5 is larger than 3. So we're done reducing.

And we're done! Here's the final answer to 100/50 + 8/12

100
50
+
8
12
=
8
3
© 2014 Randy Tayler