Mathematics for IGCSE & O level - Probability (Section 4)
1
If the probability of an event occurring is 0.25, what is the probability of that event *not* occurring?
إجابة
(C)
0.75
2
Which of the following are correct when dealing with dependent events?
إجابة
A
B
D
3
Which statement about probability is true?
إجابة
(C)
The probability of an event is always a number between 0 and 1, inclusive.
4
Which of the following scenarios represents independent events?
إجابة
(B)
Flipping a coin and then rolling a die.
5
In a school, 60% of the students are girls and 40% are boys. What is the probability of randomly selecting a boy?
إجابة
(A)
0.4
6
A box contains 3 red, 4 blue and 2 green balls. What is the probability of choosing a blue ball?
إجابة
(B)
4/9
7
A jar contains 4 red, 5 blue and 3 green marbles. What is the probability of drawing a marble that is not red?
إجابة
(D)
7/12
8
What is the expected frequency?
إجابة
(C)
Number of trials multiplied by the probability of the event occurring
9
In a standard deck of cards, are the events of drawing a King and drawing a Spade mutually exclusive?
إجابة
(B)
No, because the King of Spades is a possible outcome.
10
If the probability of winning the first hockey match is 0.6, and if they win the first match, the probability of winning the second is 0.7, otherwise 0.4. What is the probability they win one of the first two matches?
إجابة
(A)
0.66
11
In a bag with 6 red balls and 4 black balls. What is the probability of selecting one of each color, if the ball is not replaced?
إجابة
(C)
12/20
12
What are the odds in favor of rolling an even number on a standard six-sided die?
إجابة
(C)
1:1
13
If the probability of an event is 0.75, what is the probability that the event will *not* occur?
إجابة
(A)
0.25
14
A basket contains 7 apples and 3 oranges. If a piece of fruit is selected at random, what is the probability it is an apple?
إجابة
(B)
7/10
15
In a school, 70% of the students are female. If a student is chosen at random, what's the probability the student is male?
إجابة
(A)
0.3
16
What is the relative frequency of an event?
إجابة
(A)
number of times an outcome occurs / total number of trials
17
If the first ball chosen from a bag is not replaced, the second draw is an example of what?
إجابة
(B)
Dependent events
18
If a fair six-sided die is rolled, what is the probability of rolling a number greater than 4?
إجابة
(A)
1/6
19
A bag contains 4 red and 6 white marbles. If a marble is selected randomly, what is the probability that it is white?
إجابة
(B)
3/5
20
What is the probability of drawing a black card (club or spade) from a standard deck of 52 playing cards?
إجابة
(A)
1/2
21
What are the values that probability can have?
إجابة
(D)
both b and c
22
If the probability of an event occurring is 0.8, what are the odds against that event happening?
إجابة
(B)
4:1
23
A spinner has 5 equal sections: red, blue, green, yellow, and purple. What is the probability of spinning either red or blue?
إجابة
(B)
2/5
24
What is relative frequency an estimate of?
إجابة
(A)
probability
25
which method is useful for solving problems with dependent events?
إجابة
(C)
Tree diagrams
26
If the probability of an event is 0, what does that mean?
إجابة
(C)
The event is impossible.
27
Given that the probability of Sarah's bus being late on any day is 0.2. What is the probability that Sarah's bus is late on both of two days?
إجابة
(B)
0.04
28
What is the result of the calculation: 1 - P(event occurring)?
إجابة
(C)
Probability of event not occurring.
29
Which events are mutually exclusive when rolling a die and flipping a coin?
إجابة
B
C
30
A bag contains 6 blue balls and 4 red balls. If a ball is chosen at random, what is the probability of selecting a red ball?
إجابة
(B)
2/5
31
For independent events A and B, the probability of both A and B occurring is calculated by:
إجابة
(C)
P(A) x P(B)
32
What is the complement of the event "rolling an even number" on a die?
إجابة
(A)
Rolling an odd number
33
If two events are independent, how do you calculate the probability of both events occurring?
إجابة
(B)
Multiply the probabilities of each event.
34
Which of the following statement(s) is/are correct regarding a probability tree diagram?
إجابة
A
C
35
What is the probability of drawing a red ball on the first draw, not replacing it, and drawing a yellow ball on the second draw if there are 7 red balls and 3 yellow balls?
إجابة
(B)
3/10
36
A bag contains 4 red marbles and 6 blue marbles. Which events are *independent* if you draw two marbles with replacement?
إجابة
A
B
C
37
What type of diagram can illustrate the outcomes and probabilities of two or more events?
إجابة
(C)
Probability Tree Diagram
38
If two events, A and B, are mutually exclusive and P(A) = 0.3 and P(B) = 0.4, what is P(A or B)?
إجابة
(B)
0.7
39
A standard deck of cards is shuffled. What is the probability of drawing a card that is a Queen?
إجابة
(B)
1/13
40
A die is rolled. What is the probability of rolling a number less than 5?
إجابة
(C)
2/3
41
If the probability of an event occurring is 0.3 and the probability of a second independent event occurring is 0.4, what is the probability of both events occurring?
إجابة
(B)
0.12
42
In a bag, there are 5 red marbles, 3 blue marbles, and 2 green marbles. What is the probability of randomly selecting a marble that is either red or blue?
إجابة
(D)
8/10
43
The probability of a certain event occurring is 0.6. What is the probability of this event *not* occurring?
إجابة
(B)
0.4
44
In the context of probability, what does 'mutually exclusive' mean?
إجابة
(B)
The events cannot occur at the same time.
45
What is the complement of the event 'rolling an even number' on a six-sided die?
إجابة
(B)
Rolling an odd number
46
What is the probability of drawing a face card (Jack, Queen, or King) from a standard deck of 52 playing cards?
إجابة
(C)
3/13
47
What is the probability of rolling a 7 with two standard six-sided dice?
إجابة
(A)
1/6
48
Consider a survey about favorite ice cream flavors. 30 people chose chocolate, 20 chose vanilla, and 10 chose strawberry. If a person is randomly selected, what is the probability that the person chose chocolate?
إجابة
(C)
1/2
49
A spinner has 4 equal sections colored red, blue, green, and yellow. What is the probability that the spinner lands on a color that is not red?
إجابة
(C)
3/4
50
A sample space diagram is a two-way table listing all possible outcomes of what?
