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A-Level MathematicsYear 2021Q1

2   1. (a) State one disadvantage of using quota sampling compared with simple random sampling. (1) In a university 8% of students are members of the university dance club. A random sample of 36 students is taken from the university. The random variable X represents the number of these students who are members of the dance club. (b) Using a suitable model for X, find (i) P(X = 4) (ii) P(X  7) (3) Only 40% of the university dance club members can dance the tango. (c) Find the probability that a student is a member of the university dance club and can dance the tango. (1) A random sample of 50 students is taken from the university. (d) Find the probability that fewer than 3 of these students are members of the university dance club and can dance the tango. (2) _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________ _____________________________________________________________________________________

Paper Source:9MA0_31_que_20211019.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)