PROBABILITY – EXPLANATION AND 15 MCQs
PART 1: EXPLANATION OF PROBABILITY
1. Meaning of Probability
Probability is the branch of mathematics that deals with the chance of occurrence of an
event. It tells us how likely something is to happen. The value of probability lies between 0
and 1. 0 means an impossible event and 1 means a certain event.
2. Important Terms
• Experiment: An action that produces outcomes (e.g., tossing a coin).
• Outcome: The result of an experiment (e.g., Head or Tail).
• Sample Space (S): The set of all possible outcomes.
• Event (E): A subset of the sample space.
3. Formula of Probability
P(E) = Number of favourable outcomes / Total number of outcomes
4. Examples
• Probability of getting Head when tossing a coin = 1/2
• Probability of getting an even number on a dice = 3/6 = 1/2
5. Types of Events
• Impossible Event: Probability = 0 (e.g., getting 7 on a normal dice).
• Certain Event: Probability = 1 (e.g., getting a number less than 7 on dice).
• Complementary Event: P(Not E) = 1 − P(E)
PART 1: EXPLANATION OF PROBABILITY
1. Meaning of Probability
Probability is the branch of mathematics that deals with the chance of occurrence of an
event. It tells us how likely something is to happen. The value of probability lies between 0
and 1. 0 means an impossible event and 1 means a certain event.
2. Important Terms
• Experiment: An action that produces outcomes (e.g., tossing a coin).
• Outcome: The result of an experiment (e.g., Head or Tail).
• Sample Space (S): The set of all possible outcomes.
• Event (E): A subset of the sample space.
3. Formula of Probability
P(E) = Number of favourable outcomes / Total number of outcomes
4. Examples
• Probability of getting Head when tossing a coin = 1/2
• Probability of getting an even number on a dice = 3/6 = 1/2
5. Types of Events
• Impossible Event: Probability = 0 (e.g., getting 7 on a normal dice).
• Certain Event: Probability = 1 (e.g., getting a number less than 7 on dice).
• Complementary Event: P(Not E) = 1 − P(E)
