Finding Probability
Calculate probability in Grade 10 math using favorable outcomes over total outcomes, applying addition and multiplication rules for compound and independent events.
Key Concepts
New Concept For equally likely outcomes, theoretical probability is the ratio of favorable to total outcomes: $P(\operatorname{event}) = \frac{\operatorname{number\;of\;favorable\;outcomes}}{\operatorname{total\;number\;of\;outcomes}}$.
Why it matters Probability is the mathematical tool for quantifying uncertainty, a skill essential for strategic decision making in fields from finance to scientific research. Mastering it allows you to model risk and predict outcomes where others only see chance.
What’s next Next, you'll apply this definition to calculate probabilities in scenarios involving geometric shapes, combinations, and both independent and dependent events.
Common Questions
What is the basic probability formula?
P(event) = number of favorable outcomes / total number of possible outcomes. For example, rolling a 3 on a die: P(3) = 1/6.
How does the addition rule work for mutually exclusive events?
P(A or B) = P(A) + P(B) when A and B cannot both occur. For non-exclusive events: P(A or B) = P(A) + P(B) - P(A and B).
How do you find the probability of two independent events both occurring?
Multiply their probabilities: P(A and B) = P(A) × P(B). For example, flipping heads twice: P(H,H) = 1/2 × 1/2 = 1/4.