26) In a relay race there are five teams A, B, C, D, E.
i) What is the probability that A, B, C finish first, second and third respectively.
ii) What is the probability that A, B, C are first three to finish (in any order).
iii) What is the probability that A and E finish first and last respectively.

Dear Student,

(i)Total number of ways A , B , C , D and E can finish the race = 5!If A, B, C  finish 1st 2nd and 3rd respectively, then D &E can finish in 2 ways.So, probability= 25!=160(ii)Number of arrangements when A,B,C  finish in top 3 = 3!Number of ways D &E can finish in bottom 2 = 2!Total number of required ways = 3!.2!So, probability= 3!.2!5!=110(iii)If A&E finish first and last place respectively , number of ways B,C &D can take remaining positions =3!So, probability= 3!5!=120

Regards,
 

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