AQA S2 2007 June — Question 4

Exam BoardAQA
ModuleS2 (Statistics 2)
Year2007
SessionJune
TopicContinuous Uniform Random Variables
TypeMeasurement error modeling

4 Students are each asked to measure the distance between two points to the nearest tenth of a metre.
  1. Given that the rounding error, \(X\) metres, in these measurements has a rectangular distribution, explain why its probability density function is $$f ( x ) = \left\{ \begin{array} { c c } 10 & - 0.05 < x \leqslant 0.05
    0 & \text { otherwise } \end{array} \right.$$
  2. Calculate \(\mathrm { P } ( - 0.01 < X < 0.02 )\).
  3. Find the mean and the standard deviation of \(X\).