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A-Level MathematicsYear 2020Q3

12 3 People buy and sell shares in companies to try to make money. Share prices can change daily and the daily percentage change of a share price can be calculated. Chidi has bought some shares in the company BASF. He has a sample of the daily percentage change of the BASF share price, summarised below: Sample size Mean Standard deviation 251 –0.163% 1.37% Using his sample and the null hypothesis H0: μ = 0, he performs a parametric hypothesis test to find out whether there is evidence that the BASF share price has a negative daily percentage change, on average. (a) Complete Chidi’s hypothesis test. You do not need to conclude in context. (5) ___________________________________________ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ ___________________________________________

Paper Source:9ST0_03_que_20201024.pdf

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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.

Syllabus levelAdvanced Level (A-Level)

SubjectMathematics

Official MarksVariable (2–6 marks)

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