8 4 A biased coin has a probability p of landing on heads, where 0 < p < 1 Simon spins the coin n times and the random variable X represents the number of heads. Taruni spins the coin m times, m ≠ n, and the random variable Y represents the number of heads. Simon and Taruni want to combine their results to find unbiased estimators of p. Simon proposes the estimator S = X Y m n + + and Taruni proposes T = 1 2 X n Y m + (a) Show that both S and T are unbiased estimators of p. (3) (b) Prove that, for all values of m and n, S is the better estimator. (4) _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________
Get full Socratic AI guidance on this question — free in the Applaa desktop app
Appy Buddy guides you step-by-step toward the answer without giving it away. Type your attempt and get instant, mark-scheme-aware clues that teach you to think like an examiner.
Join Applaa Community
Create your own games, learn AI concepts, program interactive apps, and share with a kid-safe community approved by parents. Free forever on Windows and Mac.
Available for Windows and macOS · COPPA Compliant
Exam Specification Info
This question is part of the UK A-Level Mathematics syllabus. In the actual exam, structured questions typically require linking specific keywords to gain full marks. Applaa helps you drill these topics.
While Other Kids Get an AI Head Start, Is Yours Falling Behind?
Give your child the same AI app-building, exam prep and tutoring edge — free for the first month, no credit card needed.
Join 10,000+ students building their first AI-powered apps with Applaa