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?
إجابة
(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?
إجابة
(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?
إجابة
(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?
إجابة
(D)
0.28
5
What is the sample space for flipping a coin and rolling a six sided die?
إجابة
A
B
6
Which events are independent?
إجابة
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?
إجابة
(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?
إجابة
(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?
إجابة
(A)
1/12
10
If P(A) = 0.4 and P(B) = 0.2 and the events are independent, find P(A and B).
إجابة
(C)
0.08
11
If the chance of rain tomorrow is 40%, what is the probability that it *will not* rain tomorrow?
إجابة
(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?
إجابة
(B)
2/5
13
What is the expected frequency of an event?
إجابة
(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?
إجابة
(A)
0.7
15
If the probability of an event is 0.6, what are the odds against that event occurring?
إجابة
(A)
2:3
16
What is the probability of not getting a head when tossing a fair coin?
إجابة
(C)
1/2
17
When tossing a coin twice, what is the probability of getting a head followed by a tail? (Assume fair coin)
إجابة
(A)
1/4
18
Two dice are rolled. What is the probability of rolling a sum of 2?
إجابة
(A)
1/36
19
If you roll a six-sided die, what is the probability of *not* rolling a 1?
إجابة
(C)
5/6
20
Which of the following are true about a probability distribution?
إجابة
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?
إجابة
(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?
إجابة
(A)
3/25
23
What is the probability of drawing a club from a standard deck of 52 cards?
إجابة
(C)
1/13
24
If the chance of snow tomorrow is 25%, what is the probability that it will not snow?
إجابة
(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?
إجابة
(A)
3/10
26
A bag contains 3 red, 5 blue, and 2 green marbles. What is the probability of selecting a green marble?
إجابة
(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?
إجابة
(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?
إجابة
(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?
إجابة
(A)
0.4
30
What are the possible outcomes when flipping a coin and rolling a six-sided die?
إجابة
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?
إجابة
(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?
إجابة
(A)
1/4
33
If the events are independent, P(A) = 0.6 and P(B) = 0.4, what is P(A or B)?
إجابة
(C)
0.76
34
What is the definition of 'expected frequency'?
إجابة
(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?
إجابة
(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?
إجابة
(B)
0.2
37
If the probability of a particular event happening is 0, then:
إجابة
(B)
The event is impossible.
38
What is the probability of drawing a red card from a standard deck of 52 playing cards?
إجابة
(B)
1/2
39
The probability that it will rain tomorrow is 0.3. What is the probability that it will *not* rain tomorrow?
إجابة
(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?
إجابة
(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?
إجابة
(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?
إجابة
(A)
1/2
43
Two events are considered mutually exclusive when:
إجابة
(C)
They cannot both occur at the same time.
44
What is the relationship between relative frequency and probability?
إجابة
(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).
إجابة
(A)
0.8
46
If two events, A and B, are mutually exclusive, what is P(A and B)?
إجابة
(B)
0
47
What are the odds in favor of drawing a heart from a standard deck of 52 playing cards?
إجابة
(B)
1:3
48
If the chance of rain is 40%, what is the chance it will NOT rain?
إجابة
(B)
60%
49
If the probability of an event occurring is 0.3, what is the probability of the event NOT occurring?
إجابة
(B)
0.7
50
Which of the following describes the sample space of flipping a coin and then rolling a six-sided die?
