Edexcel D1 — Question 2

Exam BoardEdexcel
ModuleD1 (Decision Mathematics 1)
TopicSign Change & Interval Methods
TypeBinary Search Algorithm

2. In a television gameshow the names of 100 celebrities are listed in alphabetical order. A name is chosen at random from the list and a contestant has to guess which celebrity has been chosen. If the contestant is not correct, the host indicates whether the chosen name comes before or after the contestant's answer in the list and the contestant makes another guess. Each contestant knows all the names on the list and has to find the chosen name in as few guesses as possible.
  1. Describe a strategy which would enable the contestant to find the chosen name in as few guesses as possible.
  2. A large database with up to one million ordered entries is to be interrogated in the same way using appropriate software. Find the maximum number of interrogations that would be required for the software to find a particular entry and explain your answer.