Statistical Sampling | OCR A-Level Maths | 40 Worked Examples (H240)

A complete OCR A A-Level Mathematics (H240) worked-solutions pack on Statistical Sampling, section 2.01. Forty exam-style questions run from Easy to Challenging, each with a fully worked, mark-scheme-annotated solution using OCR’s own M/A/B mark codes and model-answer wording. Coverage is tuned to the OCR specification exactly: population and sample, census versus sample survey, sampling frames, simple random sampling and opportunity (convenience) sampling as the two methods you must carry out, plus recognising and critiquing systematic, stratified, cluster and quota sampling in context, which OCR asks you only to comment on and never to compute. Also included: designing fair random-selection mechanisms, dealing with repeats and out-of-range random numbers, informal inference from a sample, sampling variability and the effect of sample size, the link to binomial modelling, and large-data-set style questions in OCR’s vehicle-emissions context. Every working line carries an arrow annotation explaining what it does, and examiner notes flag exactly what earns and loses marks. Ideal for revision, homework or in-class worked examples. Answers in a clean, consistent house style.