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A-Level MathematicsYear 2020Q8

22 8 A circle, centre O, has radius x cm, where x is an observation from the random variable X which has a rectangular distribution on [0, π] (a) Find the probability that the area of the circle is greater than 10 cm2 (3) (b) State, giving a reason, whether the median area of the circle is greater or less than 10 cm2 (1) The triangle OAB is drawn inside the circle with OA and OB as radii of length x cm and angle AOB x radians. (c) Use algebraic integration to find the expected value of the area of triangle OAB. Give your answer as an exact value. (7) ___________________________________________ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ ___________________________________________

Paper Source:9FM0_4B_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)