Edexcel S1 — Question 5

Exam BoardEdexcel
ModuleS1 (Statistics 1)
TopicNormal Distribution
TypeIndependent events across days/trials

5. The time taken in minutes, \(T\), for a mechanic to service a bicycle follows a normal distribution with a mean of 25 minutes and a variance of 16 minutes \(^ { 2 }\). Find
  1. \(\mathrm { P } ( T < 28 )\),
  2. \(\quad \mathrm { P } ( | T - 25 | < 5 )\). One afternoon the mechanic has 3 bicycles to service.
  3. Find the probability that he will take less than 23 minutes on each of the three bicycles.
    (4 marks)