Question

An urn contains 4 green , 5 blue ,2 red and 3yellow marbles . If three marbles are drawn at random , what is the probability that none is green ? A. `(2)/(7)` B. `(253)/(728)` C. `(10)/(21)` D. none of these Select the correct answer from above options

Answer 1

Correct Answer - D According to question `n(S)=""^(14)C_(3)=(14!)/((14-3)!3!)=(14xx13xx12)/(3xx2xx1)=364` `and n( E)=""^(10)C_(3)=(10!)/((10-3)!3!)=(10xx9xx8)/(3xx2xx1)=120` `implies ` Required probability `=(N( E))/(n(S))=(120)/(364)=(30)/(91)`