[bonanova]

They say a magician never reveals his/her secrets.

Well this is your lucky day.

I'm "giving" you a cool trick today, absolutely free.

Here's how it goes ... play along as a spectator.

Please select a whole number between 51 and 100.

Got it? Good. Don't reveal it.

Please quiet your mind for ten seconds while I

channel your thoughts. Fine. Now I will write a

different number on this paper, then I will seal

it in this envelope.

Now I want you to add 76 to your number, cross

out the first digit of the sum and add that digit

to the result. Finally, subtract that sum from

your original number. Do you have your final

result? Good.

I now hand you the sealed envelope.

23

Isn't that cool?

Now you can play this trick on your friends.

And just to vary things, you don't have to use 76.

You could use other numbers. Like 62. Oh, but

then you'd have to hide a different number in the envelope.

What number should you hide?

[Guest]

38

[bonanova]

38

See if it works.

[Yoruichi-san]

37

The original:

Add 76 -> 176 > x+76 > 127, so when you "cross out the first digit", you're subtracting 100, and when you add the first digit, you're adding 1, so you get (x+76+1-100)= (x-23)

Subtracting this from your original number -> x-(x-23) = 23

Now replace 76 by 62 -> 37

Edited October 3, 2008 by Yoruichi-san

[bonanova]

37

Great channeling...

[Guest]

Nice trick indeed. I think I can explain it.

The steps we are doing are.

number+76-100+1=number-23

and then number -(number-23)=23.

so if we use 62 then we are doing number+62-100+1=number-37

so we should write 37.

[bonanova]

Nice trick indeed. I think I can explain it.

The steps we are doing are.

number+76-100+1=number-23

and then number -(number-23)=23.

so if we use 62 then we are doing number+62-100+1=number-37

so we should write 37.

Yup.

[Izzy]

Just plug in a number 51-100 and replace the 76 in the formula with 62. Same answer everytime.

[Guest]

See if it works.

Oops. Forgot the minus one.

[bonanova]

Oops. Forgot the minus one.

Yup, and I couldn't tell you with without spoiling...

Nice one.