The Official IQ Questions Thread
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Lol! This thread's on the 5th page now! Lets keep it up!
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you have 100 bottles of wine one of which is poisoned, and 24 hours to find out which one it is. the poison will take effect in 23.99999 hours. what is the minimum number of test rats that is needed to test which bottle is poisoned?
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Okay guys, I'm going to excuse myself... Work is calling!
I'll check in soon to read up and post Detached's Round 3! Keep the fire burning!
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Originally posted by skythewood:
you have 100 bottles of wine one of which is poisoned, and 24 hours to find out which one it is. the poison will take effect in 23.99999 hours. what is the minimum number of test rats that is needed to test which bottle is poisoned?
7 ah.haha
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Originally posted by ChoCoChips:
7 ah.haha
explain?
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Originally posted by skythewood:
you have 100 bottles of wine one of which is poisoned, and 24 hours to find out which one it is. the poison will take effect in 23.99999 hours. what is the minimum number of test rats that is needed to test which bottle is poisoned?
something that require binary. heard from friend before but i forgot how le.
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sth to do with binary ba.
100 gives u a 7 bit binary number ma.
assign 1 rat to a bit, eg rat 1 is assigned to the msb, rat 7 assigned to lsb.
den write down the no of each bottle in binary.
den, let's take 17.
the binary for 17 is 0010001. den make rat 3 and rat 7 drink the wine. i.e if a bit is 1, den the rat assigned to that bit must drink the wine.
do this for all the bottles lo.
after 1 day line the rats up again, in their bit order.
dead one u put 1, alive one 0.
den u'll get the number in binary.
convert back to decimal and voila!
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Originally posted by ChoCoChips:
sth to do with binary ba.
100 gives u a 7 bit binary number ma.
assign 1 rat to a bit, eg rat 1 is assigned to the msb, rat 7 assigned to lsb.
den write down the no of each bottle in binary.
den, let's take 17.
the binary for 17 is 0010001. den make rat 3 and rat 7 drink the wine. i.e if a bit is 1, den the rat assigned to that bit must drink the wine.
do this for all the bottles lo.
after 1 day line the rats up again, in their bit order.
dead one u put 1, alive one 0.
den u'll get the number in binary.
convert back to decimal and voila!
Correct!
that is the whole process... but you never show the calculation...
basically 1 rat can test 2 bottle. drink one of the bottle. if live, bottle is ok. if not, bottle is poison.
2 rat can test 4 bottle.rat 1 drink bottle 1 and 2. rat 2 drink bottle 1 and 3.
if both die, bottle 1 poison. if both live, bottle 4 poison. if rat 1 die, bottle 2 poison. if rat 2 die, bottle 3 poison.1 rat = 2 bottle
2 rat = 4
3 rat = 8
....
7 rat = 128.
minimum is 7 rats!
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There are 10 sets of 10 coins. You know how much the coins should weigh. You know all the coins in one set of ten are exactly a hundredth of an ounce off, making the entire set of ten coins a tenth of an ounce off. You also know that all the other coins weight the correct amount. You are allowed to use an extremely accurate digital weighing machine only once.
How do you determine which set of 10 coins is faulty?
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Originally posted by skythewood:
Correct!
that is the whole process... but you never show the calculation...
basically 1 rat can test 2 bottle. drink one of the bottle. if live, bottle is ok. if not, bottle is poison.
2 rat can test 4 bottle.rat 1 drink bottle 1 and 2. rat 2 drink bottle 1 and 3.
if both die, bottle 1 poison. if both live, bottle 4 poison. if rat 1 die, bottle 2 poison. if rat 2 die, bottle 3 poison.1 rat = 2 bottle
2 rat = 4
3 rat = 8
....
7 rat = 128.
minimum is 7 rats!
haha i think ur answer is more acceptable than mine.mine got use binary, den nt everybody noes binary one.
haha
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wah tt one i dunno.
haha. lets continue tml!
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Originally posted by skythewood:
There are 10 sets of 10 coins. You know how much the coins should weigh. You know all the coins in one set of ten are exactly a hundredth of an ounce off, making the entire set of ten coins a tenth of an ounce off. You also know that all the other coins weight the correct amount. You are allowed to use an extremely accurate digital weighing machine only once.
How do you determine which set of 10 coins is faulty?
i know the standard answer is take out 1 coin from 1st set, 2 coin from 2nd set and so on then weight them together. but then there is 1 loophole with this answer. you will so lucky pick out the faulty coin and weight meh?
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all ten coins in the set is faulty, so yes, you will be lucky
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freedom got the answer ah?
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Originally posted by purpledragon84:
freedom got the answer ah?
answer to the coin question?
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Originally posted by freedom4ever:
answer to the coin question?
yah.. that method a bit wrong leh.. how to know which coin is the coin that was taken frm the faulty bag, since u have 10 coins from 10 bags weighed simultaneously..
edit:which is what u question-ed too la lol..
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Originally posted by purpledragon84:
yah.. that method a bit wrong leh.. how to know which coin is the coin that was taken frm the faulty bag, since u have 10 coins from 10 bags weighed simultaneously..
edit:which is what u question-ed too la lol..
no answer to it. haha.
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take note that you know what each coin should weight, and you know the set of 10 coins is off by hundredth of an ounce.
take 1 coin from set 1, 2 coin from set 2, and so on...
total of 55 coin.
if the weight of the 55 coin is off by 1 hundredth of an ounce from what it should weight if all is perfect, set 1 is the set with all coins faulty.
is 2 hundredth of an ounce off, set 2... 3 hundredth of an ounch off, set 3....
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Same answer as freedom,
1 coin from 1st bag, 2coins from 2nd bag, etc etc....
If 1st bag is with faulty coins, the weigh will be 10 oucne off, if 2nd bag is with fault coins, weight will be 20 ounce off, etc etc.... -
Originally posted by skythewood:
take note that you know what each coin should weight, and you know the set of 10 coins is off by hundredth of an ounce.
take 1 coin from set 1, 2 coin from set 2, and so on...
total of 55 coin.
if the weight of the 55 coin is off by 1 hundredth of an ounce from what it should weight if all is perfect, set 1 is the set with all coins faulty.
is 2 hundredth of an ounce off, set 2... 3 hundredth of an ounch off, set 3....
ORH!
so wad u mean is an entire set is faulty la.
i see.
hahaha
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orh... i saw freedom's soln wrongly.. i thot 1 coin from each bag.. haha.. guess that means time to slp..
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Two planes take off at the same exact moment. They are flying across the Atlantic. One leaves New York and is flying to Paris at 500 miles per hour. The other leaves Paris and is flying to New York at only 450 miles per hour ( because of a strong head wind ). Which one will be closer to Paris when they meet?
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The one flying from paris, cause of the butt(not sure what is that call) of the plane...
of cause if your asking whereby the whole body meeting ...will be same distance
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1983 singapore dollars is worth more than 1981 singapore dollars. why?
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cause 1983* $1= $1983 while 1981 only gives you $1981