In a lottery, there are 35 tickets in all, 10 bearing prize numbers and 25 are blanks. A lady draws 2 tickets at random. What is the probability that she will win one prize.
A bag contains 3 red balls bearing numbers 1, 2, 3 (one number on one ball) ; and two black balls bearing numbers 4 and 6. A ball is drawn, its number noted and the ball is replaced in the bag. Then another ball is drawn and its number noted. Find the probability of drawing:
(i) 2 on the first draw and 6 on the second draw.
(ii) a number ≤ 2 on the first draw and 4 on the second draw.
(iii) a total of 5.
Number of digits = 10
Number of digits to be used with no repeat = Number of points in the sample space S = n(S) = 5040
Event A: right sequence of numbers is obtained.
Hence, the probability that the lock will be opened,