math help

What is 100/100 + 7/8?

What is 100/100 + 7/8?

Here's how you add

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

100/100 times 8

Now for the second term. You multiply 7 by 100, and get 700, then multiply 100 by 8 and get 800.

7/8 times 100

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

800
800
+
700
800

Step 2

Since our denominators match, we can add the numerators.

800 + 700 = 1500

That gives us the sum, which is

1500
800

Step 3

Now, do we need to simplify this fraction?

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

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

1500
800
÷ 2 =
750
400

So far so good... let's try to divide by that number again.

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

750
400
÷ 2 =
375
200

So far so good... let's try to divide by that number again.

No good. So next you try the next prime number, which is 3...

No good. So next you try the next prime number, which is 5...

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

375
200
÷ 5 =
75
40

So far so good... let's try to divide by that number again.

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

75
40
÷ 5 =
15
8

So far so good... let's try to divide by that number again.

No good. So next you try the next prime number, which is 7...

No good. So next you try the next prime number, which is 11...

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

And we're done! Here's the final answer to 100/100 + 7/8

100
100
+
7
8
=
15
8
© 2014 Randy Tayler