math help

What is 7/12 + 5/10?

What is 7/12 + 5/10?

This is how to add

7
12
+
5
10

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 7 by 10, and get 70, then we multiply 12 by 10 and get 120.

7/12 times 10

Do the same for the second term. We multiply 5 by 12, and get 60, then multiply 12 by 10 and get 120.

5/10 times 12

The problem now has new fractions to add:

70
120
+
60
120

Step 2

Since our denominators match, we can add the numerators.

70 + 60 = 130

This yields the answer

130
120

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
120
÷ 2 =
65
60

Now, try the same number again.

Nope. Try the next prime number, 3...

Nope. Try the next prime number, 5...

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

65
60
÷ 5 =
13
12

Now, try the same number again.

Nope. Try the next prime number, 7...

Nope. Try the next prime number, 11...

Nope. Try the next prime number, 13...

No good. 13 is larger than 12. So we're done reducing.

Congratulations! Here's your final answer to 7/12 + 5/10

7
12
+
5
10
=
13
12
© 2014 Randy Tayler