5. Statistics
Probability Basics — Quiz
Test your understanding of probability basics with 5 practice questions.
Practice Questions
Question 1
Given events A, B and C with probabilities P(A)=0.5, P(B)=0.4, P(C)=0.3, P(A∩B)=0.2, P(B∩C)=0.1, P(A∩C)=0.05 and P(A∩B∩C)=0.02, what is P(A ∪ B ∪ C)?
Question 2
A diagnostic test for a disease has sensitivity 90% and specificity 80%. If disease prevalence is 5%, what is the probability that a person actually has the disease given a positive test result?
Question 3
A library has 20 English and 10 French books. If a student selects 5 books at random, what is the probability exactly 3 are English?
Question 4
Two fair six-sided dice are rolled. Given that at least one die shows a 6, what is the probability that the sum of the dice is 8?
Question 5
Events A and B satisfy P(A)=0.3, P(B)=0.4 and P(A ∪ B)=0.58. Are A and B independent?