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  #1  
Old 11-15-2005, 11:24 PM
lotus776 lotus776 is offline
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Default math question...need help

1000 lockers at WENUMBEREM HS are displayed in one long row and are labeled from 1 to 1000. In addition, 1000 students are lined up in a row at locker number 1. The first student runs and opens every locker. The third student runs through and CHANGES every third locker; that is, if it is open, he closes it; if it is closed, he opens it. The fourth student runs through and CHANGES every fourth locker. This process continues until the 1000th student runs through and changes the 1000th locker.
1) At the end of this process, which numbered lockers are left open?

2) What is the pattern of numbers in (1)? BE VERY SPECIFIC!

3) what is the reasoning for this pattern? EXPLAIN IN DETAIL!

thanks for your help!
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  #2  
Old 11-15-2005, 11:27 PM
daryn daryn is offline
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Default Re: math question...need help

wrong forum, man
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  #3  
Old 11-15-2005, 11:29 PM
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Default Re: math question...need help

You need the "Do your homework yourself" forum.
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  #4  
Old 11-15-2005, 11:37 PM
BruceZ BruceZ is offline
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Default Re: math question...need help

[ QUOTE ]
1000 lockers at WENUMBEREM HS are displayed in one long row and are labeled from 1 to 1000. In addition, 1000 students are lined up in a row at locker number 1. The first student runs and opens every locker. The third student runs through and CHANGES every third locker; that is, if it is open, he closes it; if it is closed, he opens it. The fourth student runs through and CHANGES every fourth locker. This process continues until the 1000th student runs through and changes the 1000th locker.
1) At the end of this process, which numbered lockers are left open?

2) What is the pattern of numbers in (1)? BE VERY SPECIFIC!

3) what is the reasoning for this pattern? EXPLAIN IN DETAIL!

thanks for your help!

[/ QUOTE ]

Doesn't the 2nd student do anything?
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  #5  
Old 11-16-2005, 12:05 AM
Isura Isura is offline
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Posts: 69
Default Re: math question...need help

I solved this problem a long time ago... I don't feel like working it out again.

Try with 2 lockers, 3 lockers, 4 lockers, 10 lockers, etc. Try to find a pattern. It's not that hard if you try enough examples.
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  #6  
Old 11-16-2005, 12:06 AM
Isura Isura is offline
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Join Date: Aug 2004
Posts: 69
Default Re: math question...need help

[ QUOTE ]
[ QUOTE ]
1000 lockers at WENUMBEREM HS are displayed in one long row and are labeled from 1 to 1000. In addition, 1000 students are lined up in a row at locker number 1. The first student runs and opens every locker. The third student runs through and CHANGES every third locker; that is, if it is open, he closes it; if it is closed, he opens it. The fourth student runs through and CHANGES every fourth locker. This process continues until the 1000th student runs through and changes the 1000th locker.
1) At the end of this process, which numbered lockers are left open?

2) What is the pattern of numbers in (1)? BE VERY SPECIFIC!

3) what is the reasoning for this pattern? EXPLAIN IN DETAIL!

thanks for your help!

[/ QUOTE ]

Doesn't the 2nd student do anything?

[/ QUOTE ]

Yes he does.
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  #7  
Old 11-16-2005, 02:12 AM
lotus776 lotus776 is offline
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Default Re: math question...need help

sorry sorry sorry


the second student runs through and closes every second locker
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  #8  
Old 11-16-2005, 02:17 AM
lotus776 lotus776 is offline
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Default Re: math question...need help

yeah, thanks for the advice...this isn't homework, it's just a prob out of a book that I have, I try to do one a day
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  #9  
Old 11-16-2005, 02:18 AM
lotus776 lotus776 is offline
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Default Re: math question...need help

why is this the wrong forum? This is a math question and I'm in the science, math, philosophy forum...what's the prob?
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  #10  
Old 11-16-2005, 04:22 AM
ThinkQuick ThinkQuick is offline
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Default Re: math question...need help

[ QUOTE ]
why is this the wrong forum? This is a math question and I'm in the science, math, philosophy forum...what's the prob?

[/ QUOTE ]

[ QUOTE ]

You need the "Do your homework yourself" forum.

[/ QUOTE ]
that's all. s'okay tho
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