math help

What is 72/63 + 2/8?

What is 72/63 + 2/8?

Here's how you add

72
63
+
2
8

Step 1

We still have different denominators (bottom numbers), though, so we need to get a common denominator. This will make the bottom numbers match. Multiply the denominators together first. Now, multiply each numerator by the other term's denominator.

Now we multiply 72 by 8, and get 576, then we multiply 63 by 8 and get 504.

72/63 times 8

Now for the second term. You multiply 2 by 63, and get 126, then multiply 63 by 8 and get 504.

2/8 times 63

This gives us a new problem that looks like so:

576
504
+
126
504

Step 2

Since our denominators match, we can add the numerators.

576 + 126 = 702

That gives us an answer of

702
504

Step 3

Can this fraction be reduced?

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

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

702
504
÷ 2 =
351
252

Now, try the same number again.

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

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

351
252
÷ 3 =
117
84

Now, try the same number again.

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

117
84
÷ 3 =
39
28

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...

Nope. Try the next prime number, 29...

No good. 29 is larger than 28. So we're done reducing.

Congratulations! Here's your final answer to 72/63 + 2/8

72
63
+
2
8
=
39
28
© 2014 Randy Tayler