math help

What is 87/100 + 6/8?

What is 87/100 + 6/8?

Here's how you add

87
100
+
6
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 87 by 8, and get 696, then we multiply 100 by 8 and get 800.

87/100 times 8

Now for the second term. You multiply 6 by 100, and get 600, then multiply 100 by 8 and get 800.

6/8 times 100

This gives us a new problem that looks like so:

696
800
+
600
800

Step 2

Since our denominators match, we can add the numerators.

696 + 600 = 1296

That gives us an answer of

1296
800

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:

1296
800
÷ 2 =
648
400

Let's try dividing by that again...

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

648
400
÷ 2 =
324
200

Let's try dividing by that again...

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

324
200
÷ 2 =
162
100

Let's try dividing by that again...

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

162
100
÷ 2 =
81
50

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...

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

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

Nope! So now we try the next greatest prime number, 13...

Nope! So now we try the next greatest prime number, 17...

Nope! So now we try the next greatest prime number, 19...

Nope! So now we try the next greatest prime number, 23...

Nope! So now we try the next greatest prime number, 29...

Nope! So now we try the next greatest prime number, 31...

Nope! So now we try the next greatest prime number, 37...

Nope! So now we try the next greatest prime number, 41...

Nope! So now we try the next greatest prime number, 43...

Nope! So now we try the next greatest prime number, 47...

Nope! So now we try the next greatest prime number, 53...

No good. 53 is larger than 50. So we're done reducing.

There you have it! Here's the final answer to 87/100 + 6/8

87
100
+
6
8
=
81
50
© 2014 Randy Tayler