Edexcel S2 2024 January — Question 5

Exam BoardEdexcel
ModuleS2 (Statistics 2)
Year2024
SessionJanuary
TopicContinuous Uniform Random Variables
TypeBreaking/cutting problems

  1. The random variable \(W\) has a continuous uniform distribution over the interval \([ - 6 , a ]\) where \(a\) is a constant.
Given that \(\operatorname { Var } ( W ) = 27\)
  1. show that \(a = 12\) Given that \(\mathrm { P } ( W > b ) = \frac { 3 } { 5 }\)
    1. find the value of \(b\)
    2. find \(\mathrm { P } \left( - 12 < W < \frac { b } { 2 } \right)\) A piece of wood \(A B\) has length 160 cm . The wood is cut at random into 2 pieces. Each of the pieces is then cut in half. The four pieces are used to form the sides of a rectangle.
  2. Calculate the probability that the area of the rectangle is greater than \(975 \mathrm {~cm} ^ { 2 }\)