Calculations using normal random variables

Question 1

finding normal probabilities from tables

Answer 1

1. formulate the problem in terms of an observed random variable X
2. reestimate the problem in terms of a standard normal variable Z by standardising X using Z = x-mew/sigma
3. find the required area under the N(0,1) making use of tables of standard normal probabilities, symmetry and the fact total area = 1