CSS - PMS - CCE - PCS - Mathematics
Probability
A bag contains 11 white and 4 black balls. Two balls are drawn successively without replacement. What is the probability that both are white?
A. 109/210
B. 11/21
C. 11/15
D. 4/15
Correct Answer: B
P = 11/15 × 10/14 = 11/21.
CSS - PMS - CCE - PCS - Mathematics
Probability
One whole number is chosen uniformly from 1 to 35. What is the probability that it is a multiple of 4?
A. 1/4
B. 4/35
C. 27/35
D. 8/35
Correct Answer: D
There are 8 multiples of 4 among 35 numbers, giving probability 8/35.
CSS - PMS - CCE - PCS - Mathematics
Probability
A container holds 13 red counters and 9 blue counters. One counter is chosen randomly. What is the probability of red?
A. 13/9
B. 13/22
C. 9/22
D. 1/22
Correct Answer: B
Probability = 13/22 = 13/22.
CSS - PMS - CCE - PCS - Mathematics
Probability
When two fair dice are rolled, what is the probability that the total is exactly 11?
A. 1/36
B. 1/9
C. 1/18
D. 1/6
Correct Answer: C
There are 2 ordered pairs with sum 11 out of 36 equally likely pairs, so probability = 1/18.
CSS - PMS - CCE - PCS - Mathematics
Probability
A bag contains 5 white and 10 black balls. Two balls are drawn successively without replacement. What is the probability that both are white?
A. 2/21
B. 2/3
C. 1/3
D. 19/210
Correct Answer: A
P = 5/15 × 4/14 = 2/21.
CSS - PMS - CCE - PCS - Mathematics
Probability
One whole number is chosen uniformly from 1 to 29. What is the probability that it is a multiple of 4?
A. 1/4
B. 4/29
C. 22/29
D. 7/29
Correct Answer: D
There are 7 multiples of 4 among 29 numbers, giving probability 7/29.
CSS - PMS - CCE - PCS - Mathematics
Probability
A container holds 7 red counters and 4 blue counters. One counter is chosen randomly. What is the probability of red?
A. 7/11
B. 1/11
C. 4/11
D. 7/4
Correct Answer: A
Probability = 7/11 = 7/11.
CSS - PMS - CCE - PCS - Mathematics
Probability
When two fair dice are rolled, what is the probability that the total is exactly 5?
A. 1/9
B. 1/9-1
C. 1/6
D. 1/12
Correct Answer: A
There are 4 ordered pairs with sum 5 out of 36 equally likely pairs, so probability = 1/9.
CSS - PMS - CCE - PCS - Mathematics
Probability
A bag contains 7 white and 7 black balls. Two balls are drawn successively without replacement. What is the probability that both are white?
A. 3/13
B. 41/182
C. 1/2
D. 3/13-1
Correct Answer: A
P = 7/14 × 6/13 = 3/13.
CSS - PMS - CCE - PCS - Mathematics
Probability
A fair coin is tossed 4 times. What is the probability of getting tails on every toss?
A. 1/16
B. 1/4
C. 1/8
D. 1/16-1
Correct Answer: A
P(all tails)=(1/2)^4=1/16.
CSS - PMS - CCE - PCS - Mathematics
Probability
A card is selected at random from a standard deck. What is the probability of drawing a queen?
A. 1/13
B. 4/13
C. 1/52
D. 1/4
Correct Answer: A
There are 4 queens in 52 cards, so probability = 4/52 = 1/13.
CSS - PMS - CCE - PCS - Mathematics
Probability
One whole number is chosen uniformly from 1 to 23. What is the probability that it is a multiple of 4?
A. 18/23
B. 5/23
C. 4/23
D. 1/4
Correct Answer: B
There are 5 multiples of 4 among 23 numbers, giving probability 5/23.
CSS - PMS - CCE - PCS - Mathematics
Probability
A container holds 12 red counters and 12 blue counters. One counter is chosen randomly. What is the probability of red?
A. 1/2-1
B. 1/2
C. 1
D. 1/24
Correct Answer: B
Probability = 12/24 = 1/2.
CSS - PMS - CCE - PCS - Mathematics
Probability
When two fair dice are rolled, what is the probability that the total is exactly 9?
A. 1/9
B. 1/9-1
C. 1/6
D. 1/12
Correct Answer: A
There are 4 ordered pairs with sum 9 out of 36 equally likely pairs, so probability = 1/9.
CSS - PMS - CCE - PCS - Mathematics
Probability
A bag contains 9 white and 4 black balls. Two balls are drawn successively without replacement. What is the probability that both are white?
A. 71/156
B. 6/13
C. 9/13
D. 4/13
Correct Answer: B
P = 9/13 × 8/12 = 6/13.
CSS - PMS - CCE - PCS - Mathematics
Probability
A fair coin is tossed 2 times. What is the probability of getting tails on every toss?
A. 1/4-2
B. 1/4
C. 1/2
D. 1/4-1
Correct Answer: B
P(all tails)=(1/2)^2=1/4.
CSS - PMS - CCE - PCS - Mathematics
Probability
A card is selected at random from a standard deck. What is the probability of drawing a king?
A. 1/13
B. 1/4
C. 1/52
D. 4/13
Correct Answer: A
There are 4 kings in 52 cards, so probability = 4/52 = 1/13.
CSS - PMS - CCE - PCS - Mathematics
Probability
One whole number is chosen uniformly from 1 to 17. What is the probability that it is a multiple of 4?
A. 4/17-1
B. 13/17
C. 1/4
D. 4/17
Correct Answer: D
There are 4 multiples of 4 among 17 numbers, giving probability 4/17.
CSS - PMS - CCE - PCS - Mathematics
Probability
A container holds 6 red counters and 7 blue counters. One counter is chosen randomly. What is the probability of red?
A. 7/13
B. 6/7
C. 1/13
D. 6/13
Correct Answer: D
Probability = 6/13 = 6/13.
CSS - PMS - CCE - PCS - Mathematics
Probability
When two fair dice are rolled, what is the probability that the total is exactly 3?
A. 1/9
B. 1/36
C. 1/18
D. 1/6
Correct Answer: C
There are 2 ordered pairs with sum 3 out of 36 equally likely pairs, so probability = 1/18.