Edexcel A Level Maths – Statistics QUESTIONS AND CORRECT ANSWERS

Edexcel A Level Maths – Statistics QUESTIONS AND CORRECT ANSWERS Linear Regression - Answer y = axⁿ logy = loga + nlogx Exponential Regression - Answer y = ab^x logy = loga + xlogb Normal Approximation - Answer µ = np σ =√(np(1-p)) Mean - Answer ∑x ÷ n GF: ∑xf ÷ ∑f Variance - Answer (∑x²/n) - (∑x/n)² Standard Deviation - Answer √variance Histograms: Height - Answer Area = k x frequency Frequency Density - Answer frequency ÷ class width Population - Answer Whole set of items of interest. Census - Answer Observes/measures every member of a population Sample - Answer Selection of observations taken from a subset of the population which is used to find out info about the population. Sampling Frame - Answer A list of individuals (named or numbered) from whom the sample is drawn Random Sampling - Answer Every member of the population has an equal chance of being selected Systematic Sampling - Answer Every nth person is chosen.