A-Level MathematicsYear 2021Q6
18 6. The discrete random variable X has the following probability distribution x a b c P(X = x) log36 a log36 b log36 c where • a, b and c are distinct integers (a < b < c) • all the probabilities are greater than zero (a) Find (i) the value of a (ii) the value of b (iii) the value of c Show your working clearly. (5) The independent random variables X1 and X2 each have the same distribution as X (b) Find P(X1 = X2) (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)