Here's another math trick that was used as part of a beverage commercial (7 UP): http://digicc.com/fido/
You can try that link or play with it here. I will give the answer for the first 4 replies.
1) Think of a 3 or 4 digit number and write it down.
2) Scramble the digits of that number.
3) Calculate the absolute value of the difference between the two numbers from steps #1 and #2.
4) Circle one of the digits in the difference. Don't circle zero. Report the remaining digits.
5) I will respond with the value of the digit you circled.
John
You can try that link or play with it here. I will give the answer for the first 4 replies.
1) Think of a 3 or 4 digit number and write it down.
2) Scramble the digits of that number.
3) Calculate the absolute value of the difference between the two numbers from steps #1 and #2.
4) Circle one of the digits in the difference. Don't circle zero. Report the remaining digits.
5) I will respond with the value of the digit you circled.
John