We are going to play a regular “find my number” game, i.e. you announce your initial guess and following my answer ( limited to: “more “, “less” or “right!”) go on to your next guess.
Usually to reveal a number from 1 to N you need no more than log
2N guesses
in the worst case.
How many guesses are needed if I told you that my number
is a 4-digit palindrome divisible by 7 ?
Assume the worst case, of course.
(In reply to
solution and commentary by Charlie)
Regarding your remark re 4 or 5:. Everyone is entitled to demand an official approval,, like getting a RIGHT answer. IMHO this might be the case when the answers are limited to YES and NO while my puzzle explicitly mentions three valid replies.
You detailed explanation is truly appreciated.
re: solution and commentary
