- 19 Jun '04 21:53 / 2 edits

That's what it is supposed to do.*Originally posted by Mouse2***the second doesn't work. it always guesses a single-digit number (unless it is temporarily messed up for some reason)**

1) Choose a 4-digit number, eg. 9433

2) Rearrange its digits to make a another 4-digit mumber, 3934

3) Subtract the smaller number from the larger. 9433 - 3934 = 5499

4) Circle one of the digits of the resulting number. (But not '0' 'cos that's already a circle.) eg. circle '5'

5) Input into the computer the remaing 3 digits. Here, these are '4', '9', and '9'.

6) The computer will now read your mind and output which number you circled,*but only if you concentrate real hard on that number.*

. - 20 Jun '04 11:00

Do the same, and give me the three digits, i will guess the fourth digit*Originally posted by THUDandBLUNDER***That's what it is supposed to do.**

1) Choose a 4-digit number, eg. 9433

2) Rearrange its digits to make a another 4-digit mumber, 3934

3) Subtract the smaller number from the larger. 9433 - 3934 = 5499

4) Circle one of the digits of the resulting number. (But not '0' 'cos that's already a circle.) eg. circle '5'

5) Input into the computer ...[text shortened]... which number you circled,*but only if you concentrate real hard on that number.*

. - 13 Aug '04 12:49 / 1 editrule 1) For any number, the number modulo 9 is equal to the sum of its digits modulo 9

So by scrambling the digits of the original number we don't change the sum of the digits and we don't change its value modulo 9

i.e, when we take the scrambled number away from the original we have done the sum: (9x + m) - (9y + m)

Hence the answer will be 9*(x-y)

Hence we know the answer is 0 modulo 9

Knowing three of the digits of the answer, using rule 1 we can work out the fourth (modulo 9), it is 9 - (sum of 3 digits). We have to add 9 if that sum results in zero or a negative number. - 24 Aug '04 18:20 / 1 edit

Following the instructions Thud and Blunder gave, if your original number was 3622, then you would have to scramble its digits to give (eg) 6223, then you take the smaller number away from the larger to get 2601, you remove one of the digits from THIS number (eg the 6) and tell me 201 - I then tell you that the digit you removed was a 6.*Originally posted by Garrison***well i had 3622 and i picked the 6... did i mess it up somewhere?**

Did you do all that? What was your starting number?