Probability

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Probability

by heshamelaziry » Thu Aug 27, 2009 5:55 pm
Jill who lives in City C, plans to visit 3 cities L,M and S. She plans to visit each city exactly once and return to City C after 3 visits. She can visit the cities in any order. In how many different ways can she visit the 3 cities ???

Answer: 6

Please explain
Source: — Problem Solving |

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Re: Probability

by winnerhere » Fri Aug 28, 2009 12:41 am
heshamelaziry wrote:Jill who lives in City C, plans to visit 3 cities L,M and S. She plans to visit each city exactly once and return to City C after 3 visits. She can visit the cities in any order. In how many different ways can she visit the 3 cities ???

Answer: 6

Please explain
Answer is 3!
(the number of ways the three cities can be arranged)

if u dont understand,please tell me. :)

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Re: Probability

by heshamelaziry » Fri Aug 28, 2009 1:08 am
winnerhere wrote:
heshamelaziry wrote:Jill who lives in City C, plans to visit 3 cities L,M and S. She plans to visit each city exactly once and return to City C after 3 visits. She can visit the cities in any order. In how many different ways can she visit the 3 cities ???

Answer: 6

Please explain
Answer is 3!
(the number of ways the three cities can be arranged)

if u dont understand,please tell me. :)

Thank you for your help. 6 is the official answer. My work on this subject tell me it should be 9.

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by winnerhere » Fri Aug 28, 2009 1:09 am
how do u tell its nine.

if u tell , i can correct ur logic.

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by heshamelaziry » Fri Aug 28, 2009 1:20 am
winnerhere wrote:how do u tell its nine.

if u tell , i can correct ur logic.

I am sure that the correct answer is 6. How so ?

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by heshamelaziry » Fri Aug 28, 2009 1:20 am
winnerhere wrote:how do u tell its nine.

if u tell , i can correct ur logic.

I am sure that the correct answer is 6. How so ?

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by winnerhere » Fri Aug 28, 2009 1:30 am
heshamelaziry wrote:
winnerhere wrote:how do u tell its nine.

if u tell , i can correct ur logic.
I am sure that the correct answer is 6. How so ?
look the person visits all the three places and return.

consider the places are in straight line.He travels across them in different orders when they are arranged in different ways.

Three different items can be arranged is 3! ways.

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by GambitOS » Fri Aug 28, 2009 2:33 am
3! means 3!=3*2*1=6