OCR S2 2012 June — Question 2

Exam BoardOCR
ModuleS2 (Statistics 2)
Year2012
SessionJune
TopicCentral limit theorem

2
  1. For the continuous random variable \(V\), it is known that \(\mathrm { E } ( V ) = 72.0\). The mean of a random sample of 40 observations of \(V\) is denoted by \(\bar { V }\). Given that \(\mathrm { P } ( \bar { V } < 71.2 ) = 0.35\), estimate the value of \(\operatorname { Var } ( V )\).
  2. Explain why you need to use the Central Limit Theorem in part (i), and why its use is justified.