CSS - PMS - CCE - PCS - Mathematics
Probability
A box contains 7 equally likely numbered tokens, of which 6 are marked as winning. What is the probability of selecting a winning token?
A. 6/7-1
B. 1
C. 6/7
D. 1/7
Correct Answer: C
Probability = 6/7 = 6/7.
CSS - PMS - CCE - PCS - Mathematics
Probability
One integer is selected at random from 1 to 19. What is the probability that it is divisible by 6?
A. 1/6
B. 3/19
C. 16/19
D. 6/19
Correct Answer: B
There are 3 multiples of 6 from 1 to 19; probability = 3/19 = 3/19.
CSS - PMS - CCE - PCS - Mathematics
Probability
A bag has 2 red and 10 blue balls. One ball is drawn at random. What is the probability of drawing a red ball?
A. 1/12
B. 1/5
C. 1/6
D. 5/6
Correct Answer: C
Probability = favourable/total = 2/12 = 1/6.
CSS - PMS - CCE - PCS - Mathematics
Probability
A fair die is rolled once. What is the probability of getting a number greater than 3?
A. 1/2
B. 1/2-1
C. 1/6
D. 3/5
Correct Answer: A
Favourable outcomes are 4 to 6: 3 out of 6, so probability = 1/2.
CSS - PMS - CCE - PCS - Mathematics
Probability
A box contains 10 equally likely numbered tokens, of which 6 are marked as winning. What is the probability of selecting a winning token?
A. 2/5
B. 2/3
C. 3/5
D. 1/10
Correct Answer: C
Probability = 6/10 = 3/5.
CSS - PMS - CCE - PCS - Mathematics
Probability
One card is drawn from a standard 52-card deck. What is the probability of drawing a king?
A. 1/52
B. 1/13
C. 4/13
D. 1/4
Correct Answer: B
There are 4 kings among 52 cards, so probability = 4/52 = 1/13.
CSS - PMS - CCE - PCS - Mathematics
Probability
One integer is selected at random from 1 to 13. What is the probability that it is divisible by 5?
A. 2/13
B. 11/13
C. 1/5
D. 5/13
Correct Answer: A
There are 2 multiples of 5 from 1 to 13; probability = 2/13 = 2/13.
CSS - PMS - CCE - PCS - Mathematics
Probability
A bag has 4 red and 7 blue balls. One ball is drawn at random. What is the probability of drawing a red ball?
A. 1/11
B. 4/11
C. 7/11
D. 4/7
Correct Answer: B
Probability = favourable/total = 4/11 = 4/11.
CSS - PMS - CCE - PCS - Mathematics
Probability
3 fair coins are tossed. What is the probability that all are heads?
A. 3/8
B. 1/3
C. 1/6
D. 1/8
Correct Answer: D
Each head has probability 1/2; all heads = (1/2)^3 = 1/8.
CSS - PMS - CCE - PCS - Mathematics
Probability
A fair die is rolled once. What is the probability of getting a number greater than 1?
A. 1
B. 5/6-1
C. 5/6
D. 1/6
Correct Answer: C
Favourable outcomes are 2 to 6: 5 out of 6, so probability = 5/6.
CSS - PMS - CCE - PCS - Mathematics
Probability
The probability of getting a head when tossing a fair coin is:
A. 0
B. 1/4
C. 1/2
D. 1
Correct Answer: C
A: Wrong because getting head is possible. B: Wrong because a fair coin has two equal outcomes, not four. C: Correct because one favourable outcome out of two gives 1/2. D: Wrong because head is not certain in one toss.