6/2/96
A. “Think of a number.”
B. [thinks of 23]
A. “Multiply by 3. Is the result odd or even?”
B. [obtains 69] “It is odd.”
A. “Add 5, or 9, whichever you like.”
B. [adds 9, & obtains 78]
A. “Divide by 2, & add 1.”
B. [obtains 40]
A. “Multiply by 3. Is the result odd or even?”
B. [obtains 120] ”It is even.”
A. “Subtract 2, or 6, whichever you like.”
B. [subtracts 6, & obtains 114]
A. “Divide by 2, & add 29, or 38, or 47, whichever you like.”
B. [adds 38, & obtains 95]
A. “Add 19 to the original number, & tack on any figure you like.”
B. [tacks on 5, & obtains 425]
A. “Add the previous result.”
B. [obtains 520]
A. “Divide by 7, neglecting remainder.”
B. [obtains 74]
A. “Again divide by 7. How often does it go?”
B. “Ten times.”
A. “The number you thought of was 23.”
[This is an improvement on the puzzle containing the direction “Multiply by 3. Is the result odd or even?” & afterwards “Divide by 2.” Four times, in the course of it, B has the choice of certain numbers, & need not say which he uses! I don’t think this phenomenon occurs in any other such puzzle.]