Edexcel S3 2012 June — Question 7

Exam BoardEdexcel
ModuleS3 (Statistics 3)
Year2012
SessionJune
TopicLinear combinations of normal random variables
TypeComparison involving sums or multiples

7. The heights, in cm, of the male employees in a large company follow a normal distribution with mean 177 and standard deviation 5 The heights, in cm, of the female employees follow a normal distribution with mean 163 and standard deviation 4 A male employee and a female employee are chosen at random.
  1. Find the probability that the male employee is taller than the female employee. Six male employees and four female employees are chosen at random.
  2. Find the probability that their total height is less than 17 m .