Question 1 - A-Level Maths

Exam Board	Edexcel
Module	S2 (Statistics 2)
Year	2014
Session	June
Topic	Poisson Distribution
Type	Scaled time period probability

Patients arrive at a hospital accident and emergency department at random at a rate of 6 per hour.
1. Find the probability that, during any 90 minute period, the number of patients arriving at the hospital accident and emergency department is
  1. exactly 7
  2. at least 10
A patient arrives at 11.30 a.m.
Find the probability that the next patient arrives before 11.45 a.m.