Mathematics for IGCSE & O level - Probability (Section 2)
1
If two events, A and B, are independent, and the probability of A is 0.3 and the probability of B is 0.5, what is the probability of both A and B occurring?
Trả lời
(B)
0.15
2
If the probability that Rabia wins the 400-metre race is 0.3, what is the probability that she does NOT win?
Trả lời
(B)
0.7
3
If the probability that a student will pass an exam is 0.8, what is the probability that the student will fail?
Trả lời
(A)
0.2
4
If the first match is lost (probability 0.4), what is the probability they win one of the first two matches, given the following: The probability of winning the second match is 0.7 if the first match is won, otherwise it's 0.4?
Trả lời
(D)
0.28
5
What is the sample space for flipping a coin and rolling a six sided die?
Trả lời
A
B
6
Which events are independent?
Trả lời
A
C
7
A spinner is divided into 4 equal sections labeled 1, 2, 3, and 4. What is the probability of spinning a number greater than 2?
Trả lời
(B)
1/2
8
If the first match of the season is won by the team (probability 0.6), what is the probability they win at least one of the first two matches, given the following: The probability of winning the second match is 0.7 if the first match is won, otherwise it's 0.4?
Trả lời
(D)
0.66
9
A fair die is rolled twice. What is the probability of rolling a 3 on the first roll and an even number on the second roll?
Trả lời
(A)
1/12
10
If P(A) = 0.4 and P(B) = 0.2 and the events are independent, find P(A and B).
Trả lời
(C)
0.08
11
If the chance of rain tomorrow is 40%, what is the probability that it *will not* rain tomorrow?
Trả lời
(B)
0.6
12
A bag contains 4 red balls and 6 blue balls. If a ball is selected at random, what is the probability it is red?
Trả lời
(B)
2/5
13
What is the expected frequency of an event?
Trả lời
(B)
probability of an event occurring * total number of observations of an event
14
Two events are *mutually exclusive*. Event A has a probability of 0.4. Event B has a probability of 0.3. What is the probability of event A OR event B occurring?
Trả lời
(A)
0.7
15
If the probability of an event is 0.6, what are the odds against that event occurring?
Trả lời
(A)
2:3
16
What is the probability of not getting a head when tossing a fair coin?
Trả lời
(C)
1/2
17
When tossing a coin twice, what is the probability of getting a head followed by a tail? (Assume fair coin)
Trả lời
(A)
1/4
18
Two dice are rolled. What is the probability of rolling a sum of 2?
Trả lời
(A)
1/36
19
If you roll a six-sided die, what is the probability of *not* rolling a 1?
Trả lời
(C)
5/6
20
Which of the following are true about a probability distribution?
Trả lời
A
B
D
21
When the outcome of a second event depends on the outcome of the first event, the events are described as what?
Trả lời
(B)
Dependent
22
What is the probability of the first ball being green, and the second ball being blue, if there are 5 green balls, 3 red balls and 2 yellow balls and the ball is replaced?
Trả lời
(A)
3/25
23
What is the probability of drawing a club from a standard deck of 52 cards?
Trả lời
(C)
1/13
24
If the chance of snow tomorrow is 25%, what is the probability that it will not snow?
Trả lời
(C)
0.75
25
A survey of 100 people showed that 60 prefer coffee, 30 prefer tea, and 10 have no preference. What is the probability a person randomly selected from the survey prefers tea?
Trả lời
(A)
3/10
26
A bag contains 3 red, 5 blue, and 2 green marbles. What is the probability of selecting a green marble?
Trả lời
(B)
1/5
27
If the probability that it rains on Monday is 0.2 and the probability it rains on Tuesday is 0.3, what is the probability that it rains on both days, assuming the events are independent?
Trả lời
(C)
0.06
28
A spinner has 3 equal sections: labeled 1, 2, and 3. What is the probability of spinning a number greater than 1?
Trả lời
(B)
2/3
29
If a coin is tossed 100 times and lands on heads 60 times, what is the experimental probability of getting tails?
Trả lời
(A)
0.4
30
What are the possible outcomes when flipping a coin and rolling a six-sided die?
Trả lời
A
B
31
A dart is thrown at a circular target. The probability of hitting the bullseye is 0.05. What is the probability of *not* hitting the bullseye?
Trả lời
(B)
0.95
32
A spinner has four equal sections: red, blue, green, and yellow. What is the probability of the spinner landing on yellow?
Trả lời
(A)
1/4
33
If the events are independent, P(A) = 0.6 and P(B) = 0.4, what is P(A or B)?
Trả lời
(C)
0.76
34
What is the definition of 'expected frequency'?
Trả lời
(B)
probability of an event occurring multiplied by the number of trials
35
If two dice are rolled, what is the probability of getting a sum of 12?
Trả lời
(B)
1/36
36
If two events, A and B, are independent, and P(A) = 0.4 and P(B) = 0.5, what is the probability of both A and B occurring?
Trả lời
(B)
0.2
37
If the probability of a particular event happening is 0, then:
Trả lời
(B)
The event is impossible.
38
What is the probability of drawing a red card from a standard deck of 52 playing cards?
Trả lời
(B)
1/2
39
The probability that it will rain tomorrow is 0.3. What is the probability that it will *not* rain tomorrow?
Trả lời
(A)
0.7
40
A bag contains 6 red marbles and 4 blue marbles. If one marble is chosen at random, what is the probability that it is red?
Trả lời
(B)
3/5
41
If the probability of an event, A, is 0.4 and the probability of event B is 0.5, what is the probability that either A or B occurs if they are mutually exclusive?
Trả lời
(A)
0.9
42
In a standard deck of 52 cards, what is the probability of selecting a card that is a heart or a diamond?
Trả lời
(A)
1/2
43
Two events are considered mutually exclusive when:
Trả lời
(C)
They cannot both occur at the same time.
44
What is the relationship between relative frequency and probability?
Trả lời
(A)
Relative frequency is an estimate of probability.
45
Two events A and B are mutually exclusive and P(A) = 0.3, P(B) = 0.5. Find P(A or B).
Trả lời
(A)
0.8
46
If two events, A and B, are mutually exclusive, what is P(A and B)?
Trả lời
(B)
0
47
What are the odds in favor of drawing a heart from a standard deck of 52 playing cards?
Trả lời
(B)
1:3
48
If the chance of rain is 40%, what is the chance it will NOT rain?
Trả lời
(B)
60%
49
If the probability of an event occurring is 0.3, what is the probability of the event NOT occurring?
Trả lời
(B)
0.7
50
Which of the following describes the sample space of flipping a coin and then rolling a six-sided die?
