math help

What is 45/3 + 6/7?

What is 45/3 + 6/7?

Here's how you add

45
3
+
6
7

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 45 by 7, and get 315, then we multiply 3 by 7 and get 21.

45/3 times 7

Now for the second term. You multiply 6 by 3, and get 18, then multiply 3 by 7 and get 21.

6/7 times 3

This gives us a new problem that looks like so:

315
21
+
18
21

Step 2

Since our denominators match, we can add the numerators.

315 + 18 = 333

So what's the answer so far?

333
21

Step 3

Can this fraction be reduced?

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:

333
21
÷ 3 =
111
7

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...

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

Congratulations! Here's your final answer to 45/3 + 6/7

45
3
+
6
7
=
111
7
© 2014 Randy Tayler