Edexcel S2 2017 January — Question 2

Exam BoardEdexcel
ModuleS2 (Statistics 2)
Year2017
SessionJanuary
TopicContinuous Uniform Random Variables
TypeFind parameters from given statistics

2. The continuous random variable \(X\) is uniformly distributed over the interval \([ \alpha , \beta ]\) where \(\beta > \alpha\) Given that \(\mathrm { E } ( X ) = 8\)
  1. write down an equation involving \(\alpha\) and \(\beta\) Given also that \(\mathrm { P } ( X \leqslant 13 ) = 0.7\)
  2. find the value of \(\alpha\) and the value of \(\beta\)
  3. find \(\operatorname { Var } ( X )\)
  4. find \(\mathrm { P } ( 5 \leqslant X \leqslant 35 )\)