Aug/Sept 2022 ASCE-NH Newsletter Aug/Sept 2022 - Page 11

CRANIUM CHALLENGE

AUGUST / SEPTEMBER CHALLENGE

" Losing your marbles " Imagine that you have three boxes , one containing two black marbles , one containing two white marbles , and the third , one black marble and one white marble . The boxes were labeled for their contents - BB , WW , BW - but someone has switched the labels so that every box is now incorrectly labeled . You are allowed to take one marble at a time out of any box , without looking inside , and by this process of sampling , you need to determine the contents of all three boxes . What is the smallest number of drawings needed to do this ?

Optional BONUS question : Can ascertain the correct label for the last box ?
Please send you answers to Thomas Selling via e-mail : thomasselling @ me . com Correct responses will be recognized in the future issues of the New Hampshire Civil Engineer .

JUNE / JULY SOLUTION

1 politician . The first inhabitant will deny being a politician if he is a politician or if he is not a politician . Therefore , the second inhabitant is not a politician because the first inhabitant did in fact deny being a politician . If the third inhabitant is not a politician and is truthful , then the first inhabitant is a politician . If the third inhabitant is a politician and liar , then the first inhabitant would not be a politician .

Correct Answers Submi ed By :

Ben Longchamp , EIT , Daigle Engineers Dr . James P . Malley , Jr . UNH Bruce A . Thomas , P . E ., Town Engineer , Hooksett , NH
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