Table of contents
- 1. Intro to Stats and Collecting Data55m
- 2. Describing Data with Tables and Graphs1h 55m
- 3. Describing Data Numerically1h 45m
- 4. Probability2h 16m
- 5. Binomial Distribution & Discrete Random Variables2h 33m
- 6. Normal Distribution and Continuous Random Variables1h 38m
- 7. Sampling Distributions & Confidence Intervals: Mean1h 3m
- 8. Sampling Distributions & Confidence Intervals: Proportion1h 12m
- 9. Hypothesis Testing for One Sample1h 1m
- 10. Hypothesis Testing for Two Samples2h 8m
- 11. Correlation48m
- 12. Regression1h 4m
- 13. Chi-Square Tests & Goodness of Fit1h 20m
- 14. ANOVA1h 0m
4. Probability
Addition Rule
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Join thousands of students who trust us to help them ace their exams!Watch the first videoMultiple Choice
A card is drawn from a standard deck of 52 cards. What is the probability that the card is a diamond or a king?
A
0.33
B
0.31
C
0.15
D
0.85

1
Identify the total number of possible outcomes. A standard deck has 52 cards, so there are 52 possible outcomes when drawing a card.
Determine the number of favorable outcomes for drawing a diamond. There are 13 diamonds in a deck.
Determine the number of favorable outcomes for drawing a king. There are 4 kings in a deck.
Since the king of diamonds is counted in both the diamonds and kings, use the principle of inclusion-exclusion to avoid double-counting. Calculate the probability of drawing a diamond or a king using the formula: P(Diamond or King) = P(Diamond) + P(King) - P(Diamond and King).
Express the probabilities as fractions: P(Diamond) = 13/52, P(King) = 4/52, and P(Diamond and King) = 1/52. Substitute these values into the formula to find the probability of drawing a diamond or a king.
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