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A-Level MathematicsYear 2021Q3

8 3. A courier delivers parcels. The random variable X represents the number of parcels delivered successfully each day by the courier where X ~ B (400, 0.64) A random sample X1, X2, ... X100 is taken. Estimate the probability that the mean number of parcels delivered each day by the courier is greater than 257 (4) ___________________________________________ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ ___________________________________________

Paper Source:9FM0_3B_que_20211016.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)