Probability

• What is the definition of probability?

  Likelihood of an event occurring
• What is the range of probability?

  0 to 1 (or 0% to 100%)
• What is the probability of flipping a coin and getting heads?

  0.5 or 50%
• What is a sample space?

  All possible outcomes of an experiment
• What is the sample space when rolling a die?

  ${1, 2, 3, 4, 5, 6}$
• What is the sample space when flipping a coin?

  ${H, T}$
• What is an event in probability?

  A subset of the sample space
• What are the probability rules used for?

  • Help calculate likelihood of events
  • Include addition and multiplication rules
• What does the addition rule in probability state?

  P(A or B) = P(A) + P(B)
• When is the addition rule used?

  When events can't happen together
• What does the multiplication rule in probability state?

  P(A and B) = P(A) × P(B)
• When is the multiplication rule used?

  For independent events occurring together
• What is the probability of rolling a 3 on a die and flipping heads on a coin?

  $\frac{1}{12}$
• What is a simple event?

  One outcome happening
• How do you calculate the probability of a simple event?

  P(event) = Number of favorable outcomes / Total outcomes
• What is the probability of picking a blue ball from a bag with 2 blue and 3 green balls?

  $\frac{2}{5}$
• What is the probability of picking a blue or green marble from a bag with 3 blue and 2 green marbles?

  1
• What are the steps to solve probability problems?

  1. Define the event of interest
  2. Determine the sample space
  3. Calculate the probability using the formula
• What is the probability of rolling a 4 on a six-sided die?

  $\frac{1}{6}$