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A-Level MathematicsYear 2022Q3

10   3. The random variable X ~ N(5, 0.42) and the random variable Y ~ N(8, 0.12) X and Y are independent random variables. A random sample of a independent observations is taken from the distribution of X and one observation is taken from the distribution of Y The random variable W = X1 + X2 + X3 +…+ Xa + bY and has the distribution N(169, 22) Find the value of a and the value of b (6) ___________________________________________ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ Turn over 11   Question 3 continued _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ ___________________________________________ (Total for Question 3 is 6 marks)

Paper Source:9fm0-4b-que-20220628.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)