Section 9.1: Basic Probability

This section introduces the concept of probability, including basic probability rules, calculating probabilities of single and multiple events, and understanding outcomes.

Example 1: Single Event Probability

A fair die is rolled. Find the probability of rolling a 4.

Step 1: Total outcomes = 6 (1,2,3,4,5,6)

Step 2: Favorable outcomes = 1 (rolling a 4)

Probability = 1/6

Example 2: Multiple Event Probability

A coin is tossed twice. Find the probability of getting two heads.

Step 1: Total outcomes = 4 (HH, HT, TH, TT)

Step 2: Favorable outcomes = 1 (HH)

Probability = 1/4

Practice Problems

  1. Roll a die. Find the probability of rolling an even number.
  2. Draw a card from a standard deck. Probability of drawing a red card.
  3. A bag contains 3 red, 2 blue, 5 green balls. Probability of drawing a blue ball.
  4. Toss a coin 3 times. Probability of getting exactly one head.
  5. Roll two dice. Probability the sum is 7.
← Previous Next →