math help

What is 100/50 + 7/8?

What is 100/50 + 7/8?

Here's how we add

100
50
+
7
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 100 by 8, and get 800, then we multiply 50 by 8 and get 400.

100/50 times 8

Now for the second term. You multiply 7 by 50, and get 350, then multiply 50 by 8 and get 400.

7/8 times 50

This gives us a new problem that looks like so:

800
400
+
350
400

Step 2

Since our denominators match, we can add the numerators.

800 + 350 = 1150

So what's the answer so far?

1150
400

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:

1150
400
÷ 2 =
575
200

Let's try dividing by that again...

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

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

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

575
200
÷ 5 =
115
40

Let's try dividing by that again...

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

115
40
÷ 5 =
23
8

Let's try dividing by that again...

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 100/50 + 7/8

100
50
+
7
8
=
23
8
© 2014 Randy Tayler