Answer Detail: RE: there are 1000 doors that are of the open-close ty...

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Question: there are 1000 doors that are of the open-close type. When a person opens the door he closes it and then opens the other. When the first person goes he opens-closes the doors ion the multiples of 1 i.e., he opens and closes all the doors. when the second goes he opens and closes the doors 2, 4 6 8 resly. Similarly when the third one goes he does this for 3 6 9 12 15th doors resly. Find number of doors that are open at last.

April 04, 2006 09:15:00	#7
Akif	Member Since: Visitor Total Comments: N/A
RE: there are 1000 doors that are of the open-close ty...
HIi Two door will be open at last B,coz first one open all the door and close all the door accept last one second one open the door multiple of 2 so iots last door is also 1000 third one open the door multiple of 3 so its last door will be 999 so two door are left open first 1000and second 999

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