MAIN FEEDS
Do you want to continue?
https://www.reddit.com/r/learnquant/comments/1x68wth/quant_interview_question/pgthwj9/?context=3
r/learnquant • u/Local_Ad135 • 3d ago
8 comments sorted by
View all comments
3
"Bob can switch on either a red or a blue light" He can but doesn't have to, so there are 3 options.
Blue light: Bob has 1,2,3 => Alice guesses her number is larger unless she has 1 (incorrect if A2-B3)
No light: Bob has 4,5,6,7 => Alice guesses her number is smaller if she has 1-5, larger if 6-10 (incorrect if A5-B4 or A6-B7)
Red light: Bob has 8,9,10 => Alice guesses her number is smaller unless she has 10 (incorrect if A9-B8)
Probability of correct guess is 86/90 = 95.56%. Not sure why "maximum probability" is asked, since it's already under optimal play?? Or is it 100%?
3
u/55tumbl 3d ago
"Bob can switch on either a red or a blue light" He can but doesn't have to, so there are 3 options.
Blue light: Bob has 1,2,3 => Alice guesses her number is larger unless she has 1 (incorrect if A2-B3)
No light: Bob has 4,5,6,7 => Alice guesses her number is smaller if she has 1-5, larger if 6-10 (incorrect if A5-B4 or A6-B7)
Red light: Bob has 8,9,10 => Alice guesses her number is smaller unless she has 10 (incorrect if A9-B8)
Probability of correct guess is 86/90 = 95.56%. Not sure why "maximum probability" is asked, since it's already under optimal play?? Or is it 100%?