math help

What is 45/3 + 7/8?

What is 45/3 + 7/8?

Here's how to add

45
3
+
7
8

Step 1

Can you add yet? Nope! The denominators don't match. We need a common denominator. So next we take both denominators and multiply them. Next, take each numerator and multiply it by the denominator of the other term.

So, we multiply 45 by 8, and get 360, then we multiply 3 by 8 and get 24.

45/3 times 8

Now for the second term. You multiply 7 by 3, and get 21, then multiply 3 by 8 and get 24.

7/8 times 3

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

360
24
+
21
24

Step 2

Since our denominators match, we can add the numerators.

360 + 21 = 381

That gives us the sum, which is

381
24

Step 3

Now, do we need to simplify this fraction?

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

Nope! So now we try the next greatest prime number, 3...

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

381
24
÷ 3 =
127
8

Let's try dividing by that again...

Nope! So now we try the next greatest prime number, 5...

Nope! So now we try the next greatest prime number, 7...

Nope! So now we try the next greatest prime number, 11...

No good. 11 is larger than 8. So we're done reducing.

There you have it! Here's the final answer to 45/3 + 7/8

45
3
+
7
8
=
127
8
© 2014 Randy Tayler