CAIE S2 2012 November — Question 3

Exam BoardCAIE
ModuleS2 (Statistics 2)
Year2012
SessionNovember
TopicLinear combinations of normal random variables
TypeExpectation and variance with context application

3 The cost of hiring a bicycle consists of a fixed charge of 500 cents together with a charge of 3 cents per minute. The number of minutes for which people hire a bicycle has mean 142 and standard deviation 35.
  1. Find the mean and standard deviation of the amount people pay when hiring a bicycle.
  2. 6 people hire bicycles independently. Find the mean and standard deviation of the total amount paid by all 6 people.