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independent events and unions of events

Review independent events and unions of events for AP Statistics and try 2 free AP-style practice questions. 10 questions on this topic in AP Statistics · Unit 4 · Probability, Random Variables, and Probability Distributions.

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Question 1

A student argues that two mutually exclusive events must be independent: if one of them occurs, the other certainly does not, so neither influences the other. A teacher disagrees. Which of the following is correct?

Question 2

At a call centre, two independent inspections are carried out on each of the calls. The first flags a problem with probability 0.49 and the second with probability 0.25. What is the probability that AT LEAST ONE of the two inspections flags a problem?

8 more questions on this topic

Full practice for AP Statistics · Unit 4 · Probability, Random Variables, and Probability Distributions: timed tests, step-by-step explanations for every answer, and AI grading for free-response questions.

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Answer, then see why

The price of gasoline rises 10% and the quantity demanded falls 5%. What happens to total revenue?

Not quite. The answer is B.

Why the other options are wrong

AI grading for free-response

Write your FRQ answer and get it scored point by point against the AP rubric, with the line from your answer that earned or missed each point.

Question 13 / 4 pts
Part a1 / 1 pts
Point 1: Earned
Grader confidence 94% sure

Reason: Correctly identifies demand for gasoline as inelastic.

Evidence: "The price of gasoline rises and the quantity falls only a little."

Part b2 / 3 pts
Point 1: Earned
Grader confidence 91% sure

Reason: Graph shows relatively inelastic demand.

Evidence: Draws a steep demand curve.

Point 2: Earned
Grader confidence 88% sure

Reason: Correct new equilibrium price.

Evidence: Shifts supply left, P1 → P2.

Point 3: Not earned
Grader confidence 82% sure

Reason: With inelastic demand, a price increase raises total revenue.

Evidence: "Revenue goes down."

Independent events and unions of events: AP Statistics Practice Questions | S&D Academy