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Probability

Each subtopic includes About section, revision page link, 10 preview questions, and practice CTAs.

Random Experiments, Outcomes and Sample Spaces

Subtopic

Random Experiments, Outcomes and Sample Spaces under Probability for Grade 11 CBSE.

About Topic & Revision

Preview questions (no answers)

  1. 1.

    A die is thrown. What is the sample space SS for the event 'getting a number less than 1'?

    A.

    {0}\{0\}

    B.

    {1}\{1\}

    C.

    {}\{\}

    D.

    {−1}\{-1\}

  2. 2.

    In a family with 3 children, what is the sample space for the number of girls?

    A.

    {1,2,3}\{1, 2, 3\}

    B.

    {0,1,2,3}\{0, 1, 2, 3\}

    C.

    {GGG,GGB,GBB,BBB}\{GGG, GGB, GBB, BBB\}

    D.

    {B,G}\{B, G\}

  3. 3.

    A spinner has 4 colors: Red, Blue, Green, Yellow. If it is spun once, what is the size of the sample space?

    A.

    2

    B.

    4

    C.

    1

    D.

    8

Download the worksheet for Probability - Random Experiments, Outcomes and Sample Spaces to practice offline. It includes additional chapter-level practice questions.

Event

Subtopic

Event under Probability for Grade 11 CBSE.

About Topic & Revision

Preview questions (no answers)

  1. 1.

    If P(A)=14P(A) = \frac{1}{4}, what is P(A′)P(A')?

    A.

    14\frac{1}{4}

    B.

    12\frac{1}{2}

    C.

    34\frac{3}{4}

    D.

    0

  2. 2.

    If two coins are tossed, what is the probability of getting at most one tail?

    A.

    14\frac{1}{4}

    B.

    12\frac{1}{2}

    C.

    34\frac{3}{4}

    D.

    1

  3. 3.

    A die is thrown once. What is the probability of getting a number greater than or equal to 2?

    A.

    16\frac{1}{6}

    B.

    13\frac{1}{3}

    C.

    23\frac{2}{3}

    D.

    56\frac{5}{6}

Download the worksheet for Probability - Event to practice offline. It includes additional chapter-level practice questions.

Axiomatic Approach to Probability

Subtopic

Axiomatic Approach to Probability under Probability for Grade 11 CBSE.

About Topic & Revision

Preview questions (no answers)

  1. 1.

    If P(A∪B)=0.8P(A \cup B) = 0.8, P(A)=0.5P(A) = 0.5, P(B)=0.6P(B) = 0.6, then P(A∩B)P(A \cap B) is:

    A.

    0.1

    B.

    0.2

    C.

    0.3

    D.

    0.4

  2. 2.

    The probability of getting a tail in a single toss of a coin is:

    A.

    00

    B.

    0.50.5

    C.

    11

    D.

    22

  3. 3.

    If P(A)=0.4P(A) = 0.4, P(B)=0.5P(B) = 0.5, and P(A∪B)=0.9P(A \cup B) = 0.9, then the event A∩BA \cap B is:

    A.

    The whole sample space

    B.

    An impossible event

    C.

    A sure event

    D.

    None of these

Download the worksheet for Probability - Axiomatic Approach to Probability to practice offline. It includes additional chapter-level practice questions.

Probability of an event

Subtopic

Probability of an event under Probability for Grade 11 CBSE.

About Topic & Revision

Preview questions (no answers)

  1. 1.

    A coin is tossed three times. What is the probability of getting no tails?

    A.

    18\frac{1}{8}

    B.

    14\frac{1}{4}

    C.

    12\frac{1}{2}

    D.

    78\frac{7}{8}

  2. 2.

    A number is chosen from {1,2,...,30}\{1, 2, ..., 30\}. What is the probability that it is a perfect square?

    A.

    15\frac{1}{5}

    B.

    16\frac{1}{6}

    C.

    110\frac{1}{10}

    D.

    115\frac{1}{15}

  3. 3.

    A card is drawn from a well-shuffled deck of 52 cards. What is the probability of getting a club or an ace?

    A.

    413\frac{4}{13}

    B.

    1752\frac{17}{52}

    C.

    14\frac{1}{4}

    D.

    313\frac{3}{13}

Download the worksheet for Probability - Probability of an event to practice offline. It includes additional chapter-level practice questions.

Occurrence of an event

Subtopic

Occurrence of an event under Probability for Grade 11 CBSE.

About Topic & Revision

Preview questions (no answers)

  1. 1.

    In a single throw of two dice, what is the probability of getting a sum of 22?

    A.

    136\frac{1}{36}

    B.

    112\frac{1}{12}

    C.

    16\frac{1}{6}

    D.

    236\frac{2}{36}

  2. 2.

    A letter is chosen at random from the word 'MATHS'. What is the probability that it is 'M'?

    A.

    15\frac{1}{5}

    B.

    25\frac{2}{5}

    C.

    14\frac{1}{4}

    D.

    12\frac{1}{2}

  3. 3.

    If EE is an event, then P(E)+P(E′)P(E) + P(E') is equal to:

    A.

    00

    B.

    11

    C.

    0.50.5

    D.

    −1-1

Download the worksheet for Probability - Occurrence of an event to practice offline. It includes additional chapter-level practice questions.

Types of events

Subtopic

Types of events under Probability for Grade 11 CBSE.

About Topic & Revision

Preview questions (no answers)

  1. 1.

    The probability of the sample space P(S)P(S) is always:

    A.

    Maximum

    B.

    Minimum

    C.

    1

    D.

    0

  2. 2.

    If AA and BB are mutually exclusive, can they occur at the same time?

    A.

    Yes

    B.

    No

    C.

    Sometimes

    D.

    Depends on sample space

  3. 3.

    If an event is certain to occur, its probability is:

    A.

    0

    B.

    1

    C.

    0.5

    D.

    Infinite

Download the worksheet for Probability - Types of events to practice offline. It includes additional chapter-level practice questions.

Algebra of events

Subtopic

Algebra of events under Probability for Grade 11 CBSE.

About Topic & Revision

Preview questions (no answers)

  1. 1.

    A coin and a die are thrown simultaneously. What is the total number of outcomes in the sample space?

    A.

    8

    B.

    12

    C.

    36

    D.

    14

  2. 2.

    If P(A)=0.8P(A) = 0.8 and P(B)=0.5P(B) = 0.5, and P(A∩B)=0.4P(A \cap B) = 0.4, find the probability that exactly one of the events AA or BB occurs.

    A.

    0.5

    B.

    0.9

    C.

    0.4

    D.

    0.1

  3. 3.

    Which of the following values cannot be a probability of an event?

    A.

    0.001

    B.

    32\frac{3}{2}

    C.

    0.99

    D.

    23\frac{2}{3}

Download the worksheet for Probability - Algebra of events to practice offline. It includes additional chapter-level practice questions.

Mutually exclusive events

Subtopic

Mutually exclusive events under Probability for Grade 11 CBSE.

About Topic & Revision

Preview questions (no answers)

  1. 1.

    Given P(A)=0.5P(A) = 0.5 and P(B)=0.4P(B) = 0.4, if AA and BB are mutually exclusive, P(A∩B)P(A \cap B) is:

    A.

    0.90.9

    B.

    0.20.2

    C.

    00

    D.

    0.10.1

  2. 2.

    If P(A)=0.6P(A) = 0.6, P(B)=0.3P(B) = 0.3, and AA and BB are mutually exclusive, find P(A′∪B′)P(A' \cup B').

    A.

    0.90.9

    B.

    0.10.1

    C.

    1.01.0

    D.

    0.70.7

  3. 3.

    In a deck of 52 cards, the event 'Picking a Red card' and 'Picking a Club' are:

    A.

    Mutually exclusive

    B.

    Not mutually exclusive

    C.

    Identical

    D.

    Exhaustive

Download the worksheet for Probability - Mutually exclusive events to practice offline. It includes additional chapter-level practice questions.

Exhaustive events

Subtopic

Exhaustive events under Probability for Grade 11 CBSE.

About Topic & Revision

Preview questions (no answers)

  1. 1.

    Which of the following describes exhaustive events AA and BB?

    A.

    They cannot happen at the same time

    B.

    Their union covers all possible outcomes

    C.

    Their intersection is the sample space

    D.

    They have equal probabilities

  2. 2.

    The union of all elementary events of a sample space SS is:

    A.

    ∅\emptyset

    B.

    SS

    C.

    A proper subset of SS

    D.

    Dependent on the experiment

  3. 3.

    If AA and BB are mutually exclusive and exhaustive, then P(B)P(B) is equal to:

    A.

    P(A)P(A)

    B.

    1−P(A)1 - P(A)

    C.

    P(A)−1P(A) - 1

    D.

    00

Download the worksheet for Probability - Exhaustive events to practice offline. It includes additional chapter-level practice questions.

Probabilities of equally likely outcomes

Subtopic

Probabilities of equally likely outcomes under Probability for Grade 11 CBSE.

About Topic & Revision

Preview questions (no answers)

  1. 1.

    A wheel is divided into 88 equal sectors numbered 11 to 88. What is the probability that the spinner lands on an odd number?

    A.

    14\frac{1}{4}

    B.

    12\frac{1}{2}

    C.

    38\frac{3}{8}

    D.

    58\frac{5}{8}

  2. 2.

    Two dice are thrown. What is the probability that the sum of numbers is greater than 1010?

    A.

    112\frac{1}{12}

    B.

    118\frac{1}{18}

    C.

    136\frac{1}{36}

    D.

    16\frac{1}{6}

  3. 3.

    The sum of the probabilities of all elementary events of an experiment is always equal to:

    A.

    00

    B.

    0.50.5

    C.

    11

    D.

    Depends on the experiment

Download the worksheet for Probability - Probabilities of equally likely outcomes to practice offline. It includes additional chapter-level practice questions.

Probability of the event 'A or B'

Subtopic

Probability of the event 'A or B' under Probability for Grade 11 CBSE.

About Topic & Revision

Preview questions (no answers)

  1. 1.

    Given P(A)=0.3,P(B)=0.4P(A) = 0.3, P(B) = 0.4, and P(A∪B)=0.5P(A \cup B) = 0.5, find P(A∩B)P(A \cap B).

    A.

    0.2

    B.

    0.1

    C.

    0.3

    D.

    0.4

  2. 2.

    If P(A)=0.4,P(B)=0.5P(A) = 0.4, P(B) = 0.5, and P(A∩B)=0.2P(A \cap B) = 0.2, calculate P(A∪B)P(A \cup B).

    A.

    0.7

    B.

    0.9

    C.

    1.1

    D.

    0.6

  3. 3.

    A card is drawn from a 52-card deck. What is the probability that it is a 10 or a Heart?

    A.

    413\frac{4}{13}

    B.

    1752\frac{17}{52}

    C.

    1652\frac{16}{52}

    D.

    1552\frac{15}{52}

Download the worksheet for Probability - Probability of the event 'A or B' to practice offline. It includes additional chapter-level practice questions.

Probability of event 'not A'

Subtopic

Probability of event 'not A' under Probability for Grade 11 CBSE.

About Topic & Revision

Preview questions (no answers)

  1. 1.

    If P(E)=0.61P(E) = 0.61, what is the value of P(E′)P(E')?

    A.

    0.390.39

    B.

    0.490.49

    C.

    0.590.59

    D.

    0.610.61

  2. 2.

    A box has 50 bolts, and 5 are defective. What is the probability of picking a non-defective bolt?

    A.

    0.90.9

    B.

    0.10.1

    C.

    0.50.5

    D.

    0.450.45

  3. 3.

    Given P(A)=0.15P(A) = 0.15, find P(not A)P(\text{not } A).

    A.

    0.850.85

    B.

    0.150.15

    C.

    0.750.75

    D.

    0.950.95

Download the worksheet for Probability - Probability of event 'not A' to practice offline. It includes additional chapter-level practice questions.