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gamjatang
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There are 5 locks and 5 keys. What is the minimum number of 24 Nov 2005, 05:41
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Question Stats:

67% (00:09) correct 33% (00:00) wrong based on 6 sessions

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There are 5 locks and 5 keys. What is the minimum number of tries you can find the proper keys for all the 5 locks?

(1) 1
(2) 2
(3) 3
(4) 4
(5) 5



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laxieqv
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There are 5 locks and 5 keys. What is the minimum number of 24 Nov 2005, 07:38
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if luck involves ...there're minimumly 4 tries , e.g , you get the correct key for corresponding lock each try right away ...after finding 4 pairs ..the rest will be known without need to try.
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GMATT73
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There are 5 locks and 5 keys. What is the minimum number of 24 Nov 2005, 08:05
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laxieqv
if luck involves ...there're minimumly 4 tries , e.g , you get the correct key for corresponding lock each try right away ...after finding 4 pairs ..the rest will be known without need to try.
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Laxie always makes these problems appear effortless. :-D Yes, it must be 4 different tries.
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gamjatang
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There are 5 locks and 5 keys. What is the minimum number of 24 Nov 2005, 21:04
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GMATT73
laxieqv
if luck involves ...there're minimumly 4 tries , e.g , you get the correct key for corresponding lock each try right away ...after finding 4 pairs ..the rest will be known without need to try.

Laxie always makes these problems appear effortless. :-D Yes, it must be 4 different tries.
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:yes

I'm :wall
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Itzrevs
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There are 5 locks and 5 keys. What is the minimum number of 24 Dec 2005, 14:16
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5 locks & 5 keys -- Requires atleast 4 tries..

Yep Ans is 4
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TeHCM
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There are 5 locks and 5 keys. What is the minimum number of 26 Dec 2005, 12:47
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Kishore
Can someone explain how?
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As luck would have it, each time you insert a key, it would be the right one.

So we have 5 keys. If from 1st-4th time we inserted a key and it was right, there is no need to try for the 5th time because we already know the one that is left must work.



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