0 votes 0 votes An urn contains $20$ balls numbers $1,.........20$. Select $5$ balls at random, without replacement. Let X be the largest number among selected balls. Determine its p.m.f. and the probability that at least one the selected numbers is $15$ or more. Probability probability gravner engineering-mathematics + – Pooja Khatri asked Sep 24, 2018 Pooja Khatri 152 views answer comment Share Follow See 1 comment See all 1 1 comment reply srestha commented Sep 24, 2018 reply Follow Share $\binom{6}{1}.\binom{14}{4}+\binom{6}{2}.\binom{14}{3}+\binom{6}{3}.\binom{14}{2}+\binom{6}{4}.\binom{14}{1}+\binom{6}{5}$ is it? 0 votes 0 votes Please log in or register to add a comment.
0 votes 0 votes probability that at least one the selected numbers is 15 or more = 1 - ( probability of selecting 5 numbers from 1...14) = 1 - (none of the numbers selected from 15...20) = 1 - ($\frac{14C_5}{20C_5}$) !KARAN answered Sep 24, 2018 !KARAN comment Share Follow See all 0 reply Please log in or register to add a comment.