Q11
Q11 A bag contains 21 toys numbered 1 to 21. A toy is drawn and then another toy is drawn without replacement. Find the probability that both toys will show even numbers.
5/21
3/14
6/22
4/21
Q12
Q12 When 3 fair coins are tossed together, what is the probability of getting at least 2 tails?
1/2
1/3
1/4
3/4
Q13
Q13 Eleven books, consisting of five Engineering books, four Mathematics books and two Physics books, are arranged in a shelf at random. What is the probability that the books of each kind are all together?
5/1155
2/1155
3/1155
1/1155
Q14
Q14 In a race, the odds in favour of cars P, Q, R, S are 1 : 3, 1 : 4, 1 : 5 and 1 : 6 respectively. Find the probability that one of them wins the race.
9/17
114/121
319/420
27/111
Q15
Q15 A fair coin is tossed repeatedly. If head appears on the first four tosses, then the probability of appearance of tail on the fifth toss is.
1/7
1/2
3/7
2/3
Q16
Q16 Tickets numbered 1 to 30 are mixed up and then a ticket is drawn at random. What is the probability that the ticket drawn has a number which is a multiple of 3 or 5?
2/15
7/15
10/30
7/30
Q17
Q17 Three students appear at an examination of Mathematics. The probability of their success are 1/3, 1/4, 1/5 respectively. Find the probability of success of at least two.
1/6
2/5
3/4
3/5
Q18
Q18 Four boys and three girls stand in queue for an interview. The probability that they stand in alternate positions is?
1/35
1/34
1/68
1/17
Q19
Q19 Seven white balls and three black balls are randomly placed in a row. Find the probability that no two black balls are placed adjacently to each other.
7/15
2/15
3/7
2/7
Q20
Q20 A card is drawn at random from a pack of 52 cards. What is the probability that it is neither a spade nor a jack?
9/13
4/13
2/13
6/13
