Go to 1-800-Got-Junk’s website and take look its smarty Junk Genie. Take a ride if you may.

Done? and amazed?

Is it really that smart? The sneaky Junk Genie pretends to be smart by taking great advantage of the magic number 9.

Take a close look at the steps you have to take:

1. thinking of a number of 2 digits, i.e. 38;

2. subtract the 2 digits from the original number. 38 – 3 – 8 = 27

What does that mean in a math language?

A 2-digital number can be represented as X * 10 + Y. For example, 38 = 3 * 10 + 8. So a math formula of the step 2 is like this:

X * 10 + Y – X – Y = X * 9

Meaning, not matter which 2-digit number you have in mind, the result from Step 2 is always the first digit times 9. Or another words, a number that can be divided by number 9.

Now, let’s go back to the Junk Genie, take look the table that lists all types of junk you might be thinking of. The answer always falls into one of the circle below and what’s in that circle is the same type of the junk that will display in the next window.

To trick you in wonder, Junk Genie generates a different table or randomly show a table from a pool of predefined table that would represent different answer from different tryout. But no matter what table shows, the content in the circled place is always the same.