posted on Apr, 5 2015 @ 10:58 PM
"There are 12 people on an island, 11 of them weigh the same and 1 different in weight.
There is only a see saw on the island and no scales of any kind. The see saw can only be used 3 times.
Find the person who doesn't weigh the same as the others. "
Though my logic may spark a debate regarding semantics relating to the term "used"... as all terms of any riddle that are presented and left out are
used to establish the dynamics of the riddle and how it is solved, my answer should suffice.
First use of the see saw: Six people are to position themselves on each side of the see saw (12 people total). At this time, the see saw will lean to
one side (doesn't matter which side). Then, during this prolonged use of the see saw, one person from each side of the see saw will dismount at a
time. As soon as the see saw balances to even weight, we will know that the last two people to dismount do NOT weigh the same. We will note these two
people as person A and person B (with person A weighing more than person B). Have the remaining people dismount.
Second use of the see saw: Since we know person A and person B do not weigh the same (with person A weighing more than person B), we now need to know
which person weighs more or less than the remaining 10 people. For this second use of the see saw, we will weigh person A against a random person of
the crowd of 10. If they weigh the same, then we know person B weighs less than the remaining crowd of 10, for he is the anomaly. If person A weighs
more than the random person of the crowd of 10, we will know that person A is the one that weighs different than everyone else as he weighs more than
two people, making him the anomaly.
Who needs a third use when we have semantics? This was my answer after 5 minutes of hearing the riddle on Brooklyn Nine Nine. It's enough for me...
but I understand if others do not agree.
edit on 5-4-2015 by ZeroAnnihilated because: Incorrect sentence structure.