AQA D1 2010 January — Question 5

Exam BoardAQA
ModuleD1 (Decision Mathematics 1)
Year2010
SessionJanuary
TopicRoute Inspection

5 There is a one-way system in Manchester. Mia is parked at her base, \(B\), in Manchester and intends to visit four other places, \(A , C , D\) and \(E\), before returning to her base. The following table shows the distances, in kilometres, for Mia to drive between the five places \(A , B , C , D\) and \(E\). Mia wants to keep the total distance that she drives to a minimum.
\backslashbox{From}{To}\(\boldsymbol { A }\)\(\boldsymbol { B }\)\(\boldsymbol { C }\)\(D\)E
A-1.71.91.82.1
B3.1-2.51.83.7
\(\boldsymbol { C }\)3.12.9-2.74.2
\(\boldsymbol { D }\)2.02.82.1-2.3
E2.23.61.91.7-
  1. Find the length of the tour \(B E C D A B\).
  2. Find the length of the tour obtained by using the nearest neighbour algorithm starting from \(B\).
  3. Write down which of your answers to parts (a) and (b) would be the better upper bound for the total distance that Mia drives.
  4. On a particular day, the council decides to reverse the one-way system. For this day, find the length of the tour obtained by using the nearest neighbour algorithm starting from \(B\).