Lesson Notes By Weeks and Term v4 - SHS 1

PROBABILITY/CHANCE

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  3. SHS 1
  4. PROBABILITY/CHANCE

Subject: Mathematics

Class: SHS 1

Term: 2nd Term

Week: 20

Grade code: 1.4.2.LI.3

Strand code: 4

Sub-strand code: 2

Content standard code: 1.4.2.CS.1

Indicator code: 1.4.2.LI.3

Theme: MAKING SENSE OF AND USING DATA

Subtheme: PROBABILITY/CHANCE

Lesson Video

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Performance objectives

Lesson summary

Probability is the mathematics of chance. It helps us understand and quantify uncertainty. In our daily lives in Ghana, we are constantly faced with situations where the outcome is not certain. Will the trotro arrive on time? Will there be light from ECG for the entire evening? Will my favourite team, the Black Stars, win their next match? Understanding probability allows us to move from simple guessing to making informed decisions based on how likely different outcomes are. This lesson focuses on a specific type of situation: when we have two or more events that do not affect each other, known as independent events.

Lesson notes

A. What are Independent Events? Two events are independent if the outcome of one event has absolutely no effect on the outcome of the other event. Simple Example: Tossing a coin and rolling a die. Getting a 'Head' on the coin does not change the probability of rolling a '6' on the die. The two events are separate and do not influence each other. Real-life Ghanaian Example: The probability that it rains in Takoradi today is independent of the probability that a student in Navrongo passes their Core Maths exam. These events are happening in different places and have no connection. Crucial Idea: When you see the word "and" connecting two independent events, it's a signal to multiply their probabilities. B. The Multiplication Rule for Independent Events (The "AND" Rule) This rule is used when we want to find the probability of two (or more) independent events *both* happening.

Rule: If A and B are independent events, then the probability of both A and B occurring is: P(A and B) = P(A) × P(B)

Evaluation guide