Edexcel S2 2013 January — Question 4

Exam BoardEdexcel
ModuleS2 (Statistics 2)
Year2013
SessionJanuary
TopicContinuous Uniform Random Variables
TypeDerive or verify variance formula

4. The continuous random variable \(X\) is uniformly distributed over the interval \([ - 4,6 ]\).
  1. Write down the mean of \(X\).
  2. Find \(\mathrm { P } ( X \leqslant 2.4 )\)
  3. Find \(\mathrm { P } ( - 3 < X - 5 < 3 )\) The continuous random variable \(Y\) is uniformly distributed over the interval \([ a , 4 a ]\).
  4. Use integration to show that \(\mathrm { E } \left( Y ^ { 2 } \right) = 7 a ^ { 2 }\)
  5. Find \(\operatorname { Var } ( Y )\).
  6. Given that \(\mathrm { P } \left( X < \frac { 8 } { 3 } \right) = \mathrm { P } \left( Y < \frac { 8 } { 3 } \right)\), find the value of \(a\).