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I'm not sure what you mean by probability method.
I guess you're asking for total possible arrangements in both cases.

Total number of arrangements without any constraints= 16!/4

Total possible arrangements with constraints= {(3*4)*2!*14!}/4


sathik63
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Sixteen persons - \(P_1\) to \(P_{16}\)- are to be seated at a square table, which has four chairs along each side. What is the probability that \(P_7\) and \(P_{13}\) sit on two adjacent chairs on the same side?

A. 1/4
B. 1/10
C. 2/15
D. 1/20
E. 1/25

Using combination:

*Four people are seated in one side, there are 3C2 ways or 3 ways to select 2 person who always sit together.

Four side are there so total 3*4-12 ways

*Total way for selecting 2 people 16C2- 120 ways

Probability = 12/120 = 1/10 way

Can anyone solve this using Probability Method?

Posted from my mobile device
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nick1816
I'm not sure what you mean by probability method.
I guess you're asking for total possible arrangements in both cases.

Total number of arrangements without any constraints= 16!/4

Total possible arrangements with constraints= {(3*4)*2!*14!}/4


sathik63
nick1816
Sixteen persons - \(P_1\) to \(P_{16}\)- are to be seated at a square table, which has four chairs along each side. What is the probability that \(P_7\) and \(P_{13}\) sit on two adjacent chairs on the same side?

A. 1/4
B. 1/10
C. 2/15
D. 1/20
E. 1/25

Using combination:

*Four people are seated in one side, there are 3C2 ways or 3 ways to select 2 person who always sit together.

Four side are there so total 3*4-12 ways

*Total way for selecting 2 people 16C2- 120 ways

Probability = 12/120 = 1/10 way

Can anyone solve this using Probability Method?

Posted from my mobile device

Okay got it,this is what I meant. Sorry for the messed up words!
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