IIT JEE , AIEEE Forum - Mathematics , Algebra - A bag contains 50 tickets numbered 1,2,3,4,5,.........50 of which.....

akshay.khare91

since there are 50 tickets therefore total no. of ways of selecting 5
tickets are 50C_{3 .}

since we want that 3rd ticket should be 30
   and also we are arranging the tickets in ascending order
so if 3rd ticket is 30 therefore 1st and 2nd ticket should have the no.
less than 30 . i.e. from 1-29 .therefore no. of ways of selecting
first two tickets from 29 tickets = 29C₂ .
and also last two tickets should have the no. greater 30
i.e. from 31-50,therefore no. of selecting last two tickets from 20 tickets
= 20C_2.

therefore no. of favorable cases = 29C₂20C₂
probability = 29C₂20C₂ / 50C₅

therefore ans. = 551/15134..    plss rate me if u find useful!!!

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