Book Maths Puzzle

Raja has 4 tickets of a lottery for which 12 tickets were sold and 3 prices are to be given. What is the probability that Raja will win at least one price?

Read Solution (Total 2)

atleast one price... so he can get upto 3 prices
probability of getting 1 price =3C1/4C1
probability of getting 2 price =3C2/4C2
probablity of gettig 3 price= 3C3/4C3
total probability=3c1/4c1 + 3c2/4c2 + 3c3/4c3
11 years agoHelpfull: Yes(2) No(2)

Let E be the event that Raja will not won any price

n(E) = number of ways in which Raja will not won any price
= number of ways of taking 4 tickets from 12, none of them win a price
= number of ways of taking 4 tickets from 9 (=12-3)
= 9C4

n(S)= number of ways of taking 4 tickets from 12 = 12C4

Probability that Raja will not win any price = n(E)n(S)

=9C4/12C4 = 14/55

Probability that Raja will at least one price
= 1 - Probability that Raja will not win any price
=1−14/55=41/55
8 years agoHelpfull: Yes(1) No(0)

Book Other Question

A basket contains 15 apples and 10 oranges out of which 4 apples and 2 oranges are defective. If a person takes two fruits at random, what is the probability that either both are apples or both are good Six persons enter a lift on the ground floor of a nine floor apartment. Assuming that each of them independently and with equal probability can leave the lift at any floor beginning with the first, what is the probability that all the six persons are leaving the lift at different floors?