Unit 4: Statistics and Probability
Topic 4.11: Conditional Probability Questions
Practice 8 exam-style questions for IB Math AA SL Topic 4.11. Review the question stems below, then unlock the full Question Bank to access markschemes, model answers, and AI grading.
1Find2 marks
2026• Aimnova practice — 4.11.1
In a class, 18 students study French and 7 of those also study German. A French student is chosen at random. Find the probability they also study German.
Markscheme and model answer locked
Unlock Question2Find2 marks
2026• Aimnova practice — 4.11.1
P(A ∩ B) = 0.35 and P(B) = 0.5. Find P(A | B).
Markscheme and model answer locked
Unlock Question3Find2 marks
2026• Aimnova practice — 4.11.1
P(A | B) = 0.4 and P(B) = 0.45. Find P(A ∩ B).
Markscheme and model answer locked
Unlock Question4Find3 marks
2026• Aimnova practice — 4.11.1
A two-way table shows 80 people: of 48 adults, 30 prefer tea; of 32 children, 8 prefer tea. Given a person prefers tea, find the probability they are an adult.
Markscheme and model answer locked
Unlock Question5Find3 marks
2026• Aimnova practice — 4.11.1
P(A) = 0.7, P(B) = 0.4 and P(A ∪ B) = 0.85. Find P(A | B).
Markscheme and model answer locked
Unlock Question6Find2 marks
2026• Aimnova practice — 4.11.1
A bag has 5 red and 3 blue balls. Two are drawn without replacement. Given the first is red, find the probability the second is red.
Markscheme and model answer locked
Unlock Question7Find4 marks
2026• Aimnova practice — 4.11.1
A test is 95% accurate for people with a disease and gives a false positive for 8% of healthy people. 2% of the population has the disease. A person tests positive. Find the probability they have the disease.
Markscheme and model answer locked
Unlock Question8Find4 marks
2026• Aimnova practice — 4.11.1
On a tree, P(machine A) = 0.6 and P(machine B) = 0.4. A's items are faulty with probability 0.05; B's with probability 0.1.
Markscheme and model answer locked
Unlock QuestionReady to practice Topic 4.11?
Get instant AI feedback on your answers, view detailed markschemes, and track your progress across all IB Math AA SL topics.