math help

What is 72/63 + 1/3?

What is 72/63 + 1/3?

This is how to add

72
63
+
1
3

Step 1

Our denominators (bottom numbers) don't match, so we can't add yet.

63 goes into 3 evenly, so we only need to multiply one term to get a common denominator.

Multiply 1 by 21, and get 21, then we multiply 3 by 21 and get 63.

1/3 times 21

We now have a new problem, that looks like this:

72
63
+
21
63

Step 2

Since our denominators match, we can add the numerators.

72 + 21 = 93

Answer:

93
63

Step 3

Now, do we need to simplify this fraction?

First, we attempt to divide it by 2...

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

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

93
63
÷ 3 =
31
21

Now, try the same number again.

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

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

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

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

Nope. Try the next prime number, 17...

Nope. Try the next prime number, 19...

Nope. Try the next prime number, 23...

No good. 23 is larger than 21. So we're done reducing.

Congratulations! Here's your final answer to 72/63 + 1/3

72
63
+
1
3
=
31
21
© 2014 Randy Tayler