Wizard.gif (4836 bytes)The key to this magic trick is a bit of ALGEBRA.

Let's take a look at the steps one at a time using Algebra.

Step 1:
Pick a whole number from one to 10.
(
Here I don't know what you picked so I call it "x".)

Step 2:
Double this number.
(
Now I have two x's or 2x.)

Step 3:
Add 4 to this number.
(
So now I have 2x + 4.)

Step 4:
Now divide by 2.
(
Here the whole thing (2x + 4) gets divided by 2.
Half of two x's is one x , and half of 4 is 2.
So now I'm left with x + 2.
)

Step 5:
Finally, subtract your original number.
(
I have x + 2, and I take away the original x. 
(x + 2 - x = 2)
It really doesn't matter what you start with, because
I am subtracting it off right here.  That will always
leave me with
2.)

Here is what the straight math looks like:

(2x + 4) - x =
........2

2x + 4 - x   =
2
......2   

1x + 2 - x =

(1x - x) + 2 =

0 + 2 = 2

 

now you try!

  • Make your own mind reading magic trick.  The final answer
    does not have to equal 2. 

  • Be sure to include at least 5 steps.

  • Write out your directions as you would say them
    to an audience.

  • Then also write out an ALGEBRAIC explanation of why it
    works. 

magician.gif (39365 bytes)

Good Luck!  I can't wait for you to READ MY MIND!

 

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