<?xml version="1.0" encoding="UTF-8" ?>
  <resource>
  <id>8167</id>
  <path>/www/nrich/html/content/id/8167/</path>
  <resourceTypeID>5</resourceTypeID>
  <last_published>2011-02-01T00:00:01</last_published>
  <indexXML>&lt;?xml version=&quot;1.0&quot; encoding=&quot;UTF-8&quot;?&gt;
&lt;mdoxml version=&quot;1.0&quot;&gt;&lt;br&gt;&lt;/br&gt;
&lt;p&gt;&lt;span class=&quot;editorial&quot;&gt;This is the curriculum mapping page for A-level decision mathematics topics.&lt;/span&gt;&lt;/p&gt;
&lt;p&gt;&lt;br&gt;&lt;/br&gt;
 &lt;/p&gt;
&lt;table style=&quot;&quot; border=&quot;1&quot;&gt;
&lt;tbody&gt;
&lt;tr height=&quot;31&quot;&gt;
&lt;td bgcolor=&quot;#66FFFF&quot; height=&quot;31&quot; style=&quot;&quot;&gt;AREA&lt;/td&gt;
&lt;td&gt;TOPICS COVERED&lt;/td&gt;
&lt;/tr&gt;
&lt;tr height=&quot;31&quot;&gt;
&lt;td bgcolor=&quot;#66FFFF&quot; height=&quot;31&quot; style=&quot;&quot;&gt;Decision D1&lt;/td&gt;
&lt;td&gt;Algorithms; algorithms on graphs; route inspection problem; critical path analysis; linear programming; matchings.&lt;/td&gt;
&lt;/tr&gt;
&lt;tr height=&quot;31&quot;&gt;
&lt;td bgcolor=&quot;#66FFFF&quot; height=&quot;31&quot; style=&quot;&quot;&gt;Decision D2&lt;/td&gt;
&lt;td&gt;Transportation problems; allocation (assignment) problems; the travelling salesman; game theory; further linear programming, dynamic programming; flows in networks.&lt;/td&gt;
&lt;/tr&gt;
&lt;/tbody&gt;
&lt;/table&gt;
&lt;br&gt;&lt;/br&gt;
&lt;br&gt;&lt;/br&gt;
&lt;table style=&quot;&quot; border=&quot;1&quot;&gt;
&lt;colgroup&gt;
&lt;col width=&quot;400&quot;&gt;&lt;/col&gt;
&lt;col width=&quot;164&quot;&gt;&lt;/col&gt;&lt;/colgroup&gt;
&lt;tbody&gt;
&lt;tr height=&quot;31&quot;&gt;
&lt;td bgcolor=&quot;#6699FF&quot; colspan=&quot;2&quot; height=&quot;31&quot; width=&quot;400&quot; style=&quot;&quot;&gt;
&lt;div&gt;Decision D1&lt;/div&gt;
&lt;div&gt;Algorithms; algorithms on graphs; route inspection problem; critical path analysis; linear programming; matchings.&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr height=&quot;17&quot;&gt;
&lt;td bgcolor=&quot;#66FFFF&quot; colspan=&quot;2&quot; height=&quot;17&quot; width=&quot;400&quot; style=&quot;&quot;&gt;ALGORITHMS&lt;/td&gt;
&lt;/tr&gt;
&lt;tr height=&quot;34&quot;&gt;
&lt;td height=&quot;34&quot; width=&quot;400&quot; style=&quot;&quot;&gt;
&lt;p&gt;The general ideas of algorithms and the&lt;br&gt;&lt;/br&gt;
implementation of an algorithm given by a flow chart&lt;br&gt;&lt;/br&gt;
or text. Bin packing, bubble sort, quick sort, binary search.&lt;/p&gt;
&lt;/td&gt;
&lt;td width=&quot;164&quot; style=&quot;&quot;&gt;
&lt;div&gt;&lt;a href=&quot;/5956&quot;&gt;Zeller&amp;#39;s Birthday&lt;/a&gt;&lt;/div&gt;
&lt;div&gt;&lt;a href=&quot;http://nrich.maths.org/5918&quot;&gt;Flow Chart&lt;/a&gt;&lt;/div&gt;
&lt;div&gt;&lt;a href=&quot;http://nrich.maths.org/5928&quot;&gt;Procedure Solver&lt;/a&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr height=&quot;17&quot;&gt;
&lt;td bgcolor=&quot;#66FFFF&quot; colspan=&quot;2&quot; height=&quot;17&quot; width=&quot;400&quot; style=&quot;&quot;&gt;ALGORITHMS ON GRAPHS&lt;/td&gt;
&lt;/tr&gt;
&lt;tr height=&quot;17&quot;&gt;
&lt;td height=&quot;17&quot; width=&quot;400&quot; style=&quot;&quot;&gt;The minimum spanning tree (minimum connector) problem. Prim’s and Kruskal’s (greedy) algorithm. Dijkstra’s algorithm for finding the shortest path.&lt;/td&gt;
&lt;td width=&quot;164&quot; style=&quot;&quot;&gt; &lt;/td&gt;
&lt;/tr&gt;
&lt;tr height=&quot;17&quot;&gt;
&lt;td bgcolor=&quot;#66FFFF&quot; colspan=&quot;2&quot; height=&quot;17&quot; width=&quot;400&quot; style=&quot;&quot;&gt;ROUTE INSPECTION PROBLEM&lt;/td&gt;
&lt;/tr&gt;
&lt;tr height=&quot;17&quot;&gt;
&lt;td height=&quot;17&quot; width=&quot;400&quot; style=&quot;&quot;&gt;Algorithm for finding the shortest route around a network, travelling along every edge at least once and ending at the start vertex.&lt;/td&gt;
&lt;td width=&quot;164&quot; style=&quot;&quot;&gt; &lt;/td&gt;
&lt;/tr&gt;
&lt;tr height=&quot;17&quot;&gt;
&lt;td bgcolor=&quot;#66FFFF&quot; colspan=&quot;2&quot; height=&quot;17&quot; width=&quot;400&quot; style=&quot;&quot;&gt;CRITICAL PATH ANALYSIS&lt;/td&gt;
&lt;/tr&gt;
&lt;tr height=&quot;17&quot;&gt;
&lt;td height=&quot;17&quot; width=&quot;400&quot; style=&quot;&quot;&gt;Modelling of a project by an activity network, from a&lt;br&gt;&lt;/br&gt;
precedence table. Completion of the precedence table for a given activity network.&lt;br&gt;&lt;/br&gt;
Algorithm for finding the critical path. Earliest and latest event times. Earliest and latest start and finish times for activities.&lt;br&gt;&lt;/br&gt;
Total float. Gantt (cascade) charts. Scheduling.&lt;/td&gt;
&lt;td width=&quot;164&quot; style=&quot;&quot;&gt; &lt;/td&gt;
&lt;/tr&gt;
&lt;tr height=&quot;17&quot;&gt;
&lt;td bgcolor=&quot;#66FFFF&quot; colspan=&quot;2&quot; height=&quot;17&quot; width=&quot;400&quot; style=&quot;&quot;&gt;LINEAR PROGRAMMING&lt;/td&gt;
&lt;/tr&gt;
&lt;tr height=&quot;17&quot;&gt;
&lt;td height=&quot;17&quot; width=&quot;400&quot; style=&quot;&quot;&gt;Formulation of problems as linear programs.&lt;br&gt;&lt;/br&gt;
Graphical solution of two variable problems using&lt;br&gt;&lt;/br&gt;
ruler and vertex methods&lt;br&gt;&lt;/br&gt;
Consideration of problems where solutions must&lt;br&gt;&lt;/br&gt;
have integer values.&lt;/td&gt;
&lt;td width=&quot;164&quot; style=&quot;&quot;&gt; &lt;/td&gt;
&lt;/tr&gt;
&lt;tr height=&quot;17&quot;&gt;
&lt;td bgcolor=&quot;#66FFFF&quot; colspan=&quot;2&quot; height=&quot;17&quot; width=&quot;400&quot; style=&quot;&quot;&gt;MATCHINGS&lt;/td&gt;
&lt;/tr&gt;
&lt;tr height=&quot;17&quot;&gt;
&lt;td height=&quot;17&quot; width=&quot;400&quot; style=&quot;&quot;&gt;Use of bipartite graphs for modelling matchings.&lt;br&gt;&lt;/br&gt;
Complete matchings and maximal matchings.&lt;br&gt;&lt;/br&gt;
Algorithm for obtaining a maximum matching.&lt;/td&gt;
&lt;td&gt; &lt;/td&gt;
&lt;/tr&gt;
&lt;/tbody&gt;
&lt;/table&gt;
&lt;p&gt; &lt;/p&gt;
&lt;p&gt; &lt;/p&gt;
&lt;table style=&quot;&quot; border=&quot;1&quot;&gt;
&lt;colgroup&gt;
&lt;col width=&quot;400&quot;&gt;&lt;/col&gt;
&lt;col width=&quot;164&quot;&gt;&lt;/col&gt;&lt;/colgroup&gt;
&lt;tbody&gt;
&lt;tr height=&quot;31&quot;&gt;
&lt;td bgcolor=&quot;#6699FF&quot; colspan=&quot;2&quot; height=&quot;31&quot; width=&quot;400&quot; style=&quot;&quot;&gt;
&lt;div&gt;Decision D2&lt;/div&gt;
&lt;div&gt;Transportation problems; allocation (assignment) problems; the travelling salesman; game theory; further linear programming, dynamic programming; flows in networks.&lt;/div&gt;
&lt;div&gt; &lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr height=&quot;17&quot;&gt;
&lt;td bgcolor=&quot;#66FFFF&quot; colspan=&quot;2&quot; height=&quot;17&quot; width=&quot;400&quot; style=&quot;&quot;&gt;TRANSPORTATION PROBLEMS&lt;/td&gt;
&lt;/tr&gt;
&lt;tr height=&quot;34&quot;&gt;
&lt;td height=&quot;34&quot; width=&quot;400&quot; style=&quot;&quot;&gt;The north-west corner method for finding an initial&lt;br&gt;&lt;/br&gt;
basic feasible solution.Use of the stepping-stone method for obtaining an&lt;br&gt;&lt;/br&gt;
improved solution. Improvement indices.Formulation as a linear programming problem.&lt;/td&gt;
&lt;td width=&quot;164&quot; style=&quot;&quot;&gt;
&lt;div&gt; &lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr height=&quot;17&quot;&gt;
&lt;td bgcolor=&quot;#66FFFF&quot; colspan=&quot;2&quot; height=&quot;17&quot; width=&quot;400&quot; style=&quot;&quot;&gt;ALLOCATION ( ASSIGNMENT) PROBLEMS&lt;/td&gt;
&lt;/tr&gt;
&lt;tr height=&quot;17&quot;&gt;
&lt;td height=&quot;17&quot; width=&quot;400&quot; style=&quot;&quot;&gt;Cost matrix reduction.Use of the Hungarian algorithm to find least cost&lt;br&gt;&lt;/br&gt;
allocation.Modification of method to deal with a maximum&lt;br&gt;&lt;/br&gt;
profit allocation.Formulation as a linear programming problem.&lt;/td&gt;
&lt;td width=&quot;164&quot; style=&quot;&quot;&gt; &lt;/td&gt;
&lt;/tr&gt;
&lt;tr height=&quot;17&quot;&gt;
&lt;td bgcolor=&quot;#66FFFF&quot; colspan=&quot;2&quot; height=&quot;17&quot; width=&quot;400&quot; style=&quot;&quot;&gt;TRAVELLING SALESMAN&lt;/td&gt;
&lt;/tr&gt;
&lt;tr height=&quot;17&quot;&gt;
&lt;td height=&quot;17&quot; width=&quot;400&quot; style=&quot;&quot;&gt;The practical and classical problems. The classical&lt;br&gt;&lt;/br&gt;
problem for complete graphs satisfying the triangle&lt;br&gt;&lt;/br&gt;
inequality.Determination of upper and lower bounds using&lt;br&gt;&lt;/br&gt;
minimum spanning tree methods.The nearest neighbour algorithm.&lt;/td&gt;
&lt;td width=&quot;164&quot; style=&quot;&quot;&gt; &lt;/td&gt;
&lt;/tr&gt;
&lt;tr height=&quot;17&quot;&gt;
&lt;td bgcolor=&quot;#66FFFF&quot; colspan=&quot;2&quot; height=&quot;17&quot; width=&quot;400&quot; style=&quot;&quot;&gt;GAME THEORY&lt;/td&gt;
&lt;/tr&gt;
&lt;tr height=&quot;17&quot;&gt;
&lt;td height=&quot;17&quot; width=&quot;400&quot; style=&quot;&quot;&gt;Two person zero-sum games and the pay-off matrix.&lt;br&gt;&lt;/br&gt;
Identification of play safe strategies and stable&lt;br&gt;&lt;/br&gt;
solutions (saddle points).Reduction of pay-off matrices using dominance&lt;br&gt;&lt;/br&gt;
arguments. Optimal mixed strategies for a game&lt;br&gt;&lt;/br&gt;
with no stable solution.Conversion of 3 × 2 and 3 × 3 games to linear&lt;br&gt;&lt;/br&gt;
programming problems.&lt;/td&gt;
&lt;td width=&quot;164&quot; style=&quot;&quot;&gt; &lt;/td&gt;
&lt;/tr&gt;
&lt;tr height=&quot;17&quot;&gt;
&lt;td bgcolor=&quot;#66FFFF&quot; colspan=&quot;2&quot; height=&quot;17&quot; width=&quot;400&quot; style=&quot;&quot;&gt;FURTHER LINEAR PROGRAMMING&lt;/td&gt;
&lt;/tr&gt;
&lt;tr height=&quot;17&quot;&gt;
&lt;td height=&quot;17&quot; width=&quot;400&quot; style=&quot;&quot;&gt;
&lt;p&gt;Formulation of problems as linear programs.&lt;/p&gt;
&lt;p&gt;The Simplex algorithm and tableau for maximising&lt;br&gt;&lt;/br&gt;
problems.The use and meaning of slack variables.&lt;/p&gt;
&lt;/td&gt;
&lt;td width=&quot;164&quot; style=&quot;&quot;&gt; &lt;/td&gt;
&lt;/tr&gt;
&lt;tr height=&quot;17&quot;&gt;
&lt;td bgcolor=&quot;#66FFFF&quot; colspan=&quot;2&quot; height=&quot;17&quot; width=&quot;400&quot; style=&quot;&quot;&gt;DYNAMIC PROGRAMMING&lt;/td&gt;
&lt;/tr&gt;
&lt;tr height=&quot;17&quot;&gt;
&lt;td height=&quot;17&quot; width=&quot;400&quot; style=&quot;&quot;&gt;Principles of dynamic programming. Bellman’s&lt;br&gt;&lt;/br&gt;
principle of optimality.Stage variables and State variables. Use of tabulation to solve maximum, minimum, minimax or maximin problems.&lt;/td&gt;
&lt;td&gt; &lt;/td&gt;
&lt;/tr&gt;
&lt;tr height=&quot;17&quot;&gt;
&lt;td bgcolor=&quot;#66FFFF&quot; colspan=&quot;2&quot; height=&quot;17&quot; width=&quot;400&quot; style=&quot;&quot;&gt;FLOWS IN NETWORKS&lt;/td&gt;
&lt;/tr&gt;
&lt;tr height=&quot;17&quot;&gt;
&lt;td height=&quot;17&quot; width=&quot;400&quot; style=&quot;&quot;&gt;Algorithm for finding a maximum flow. Cuts and their capacity. Use of the max flow — min cut theorem to verify that a flow is a maximum flow. Multiple sources and sinks.&lt;/td&gt;
&lt;td&gt; &lt;/td&gt;
&lt;/tr&gt;
&lt;/tbody&gt;
&lt;/table&gt;
&lt;p&gt; &lt;/p&gt;
&lt;p&gt;NOTE: These NRICH problems often draw together strands from decision mathematics as a whole, and any one activity may have several possible lesson foci. For example, some problems will work well either as introduction to a topic to raise the underlying issues or as an end of module consolidation in which students&amp;#39; problem solving and understanding is drawn together. Others are suitable for
classroom discussion and others for individual problem solving.&lt;br&gt;&lt;/br&gt;
&lt;br&gt;&lt;/br&gt;
&lt;br&gt;&lt;/br&gt;
&lt;span style=&quot;font-style: italic;&quot;&gt;The topics are grouped according to a summary of the Edexcel schemes, but should be generally of use.&lt;/span&gt; &lt;span style=&quot;font-style: italic;&quot;&gt;Please note that this material is under development. New problems will arrive on a regular basis and it is intended that detailed teachers&amp;#39; notes will eventually accompany all of the problems. If you have any comments
please do get in touch&lt;/span&gt;.&lt;br&gt;&lt;/br&gt;
 &lt;/p&gt;&lt;/mdoxml&gt;</indexXML>
  <solutionXML/>
  <noteXML/>
  <clueXML/>
  <canonXML/>
  <end_user_role>0</end_user_role>
  <difficulty>3</difficulty>
  <keystage1>0</keystage1>
  <keystage2>0</keystage2>
  <keystage3>0</keystage3>
  <keystage4>0</keystage4>
  <keystage4plus>1</keystage4plus>
  <title>Curriculum mapping for decision mathematics</title>
  <description>This is the curriculum mapping page for decision modules</description>
</resource>