Probability questions reward a good diagram. Venn diagrams, tree diagrams and two-way tables turn wordy questions into arithmetic; Year 13 adds conditional probability and set notation.
Start with one question on probability. Stuck? Take a hint. No sign-in needed.
The probability that it rains tomorrow is \(\frac{7}{20}\). Find the probability that it does not rain.
In a class of \(30\), \(18\) study French, \(12\) study Spanish and \(5\) study both. A student is chosen at random. Find the probability that they study neither.
\(P(A) = \frac{1}{5}\), \(P(B \mid A) = \frac{3}{4}\) and \(P(B \mid A') = \frac{1}{8}\). Find \(P(A \mid B)\).
Two fair six-sided dice are rolled. Find the probability that the total is \(9\).
In a class of \(40\), \(25\) study French, \(20\) study Spanish and \(10\) study both. A student is chosen at random. Find the probability that they study neither.
Every board examines the same A Level Maths content, set by the Department for Education. Only the paper it appears on and the section numbering differ.
Three examples from the question bank, one with its full mark scheme open. Every question comes with a step-by-step mark scheme (M, A and B marks) once you start practising.
Question 1easy2 marks
Events $A$ and $B$ are mutually exclusive. Given that $P(A) = 0.3$ and $P(B) = 0.45$, find $P(A \cup B)$.
Given that $P(A) = 0.5$, $P(B) = 0.6$, and $P(A \cup B) = 0.85$, find $P(A \cap B)$.
Full worked solution Free, no sign-in
M1 for using the general addition rule: $P(A \cup B) = P(A) + P(B) - P(A \cap B)$.
M1 for substituting the known values: $0.85 = 0.5 + 0.6 - P(A \cap B)$.
A1 for solving to find $P(A \cap B) = 1.1 - 0.85 = 0.25$.
Every question here has a full worked solution.See them all →
Question 3hard3 marks
The probability that it rains on a given day is $0.4$. If it rains, the probability that Alice takes the bus is $0.8$. If it does not rain, the probability that she takes the bus is $0.3$. Given that Alice takes the bus, find the probability that it rained that day.
These skills sit in the Statistics unit of the UK A Level practice engine. Pick any mix of them, set the difficulty, and check each answer against its mark scheme.
Basic probability & sample spaceVenn diagramsMutually exclusive & independent eventsConditional probabilityProbability tree diagramsTwo-way tables
Probability can come up on these papers (from each board's paper structure). We haven't mapped individual questions yet, so open a recent paper and look for it.
Is probability on the AQA, Edexcel and OCR A Level Maths exams?
Yes. Probability is part of the A Level Maths content that every board examines: AQA section M, Edexcel Statistics 3, OCR 2.03. It is assessed in AQA Paper 3; Edexcel Paper 3, Section A; OCR A Paper 2, statistics section.
Is probability Year 12 or Year 13 content?
Both. The AS content, usually taught in Year 12, is: Mutually exclusive and independent events; Venn diagrams, tree diagrams and two-way tables. The full A Level adds: Conditional probability, including set notation P(A | B); Modelling with probability and questioning the assumptions.
How do I show two events are independent?
Show that P(A ∩ B) = P(A) × P(B), or that P(A | B) = P(A). Say which one you are testing and write a conclusion.