Foreign currency exchange

Foreign currency exchange

Pencil and paper
Overview
Using this Resource
Connecting to the Curriculum
Marking Student Responses
Working with Students
Further Resources
This task is about completing a table about a number pattern.

various-currencies-arb.png


The bank charges twenty New Zealand dollars (NZ$20) to send money to the United States of America, for any amount of money sent. 

In 1999, two New Zealand dollars (NZ$2) bought one United States dollar (US$1).
 

a) Complete the table to show the cost in NZ dollars (NZ$), including bank charges, of sending the different US dollar (US$) amounts.
 
US$ 40 80 120 160 200
NZ$ 100 180      
 
b)
 
Complete the sentence to describe the rule giving the full NZ dollar cost of sending money to the United States of America.
 
Multiply the number of US dollars by __________ and then __________ .
 
c)		  
On the graph below, plot the values from the table above.
 
 


d)		  
From your graph, estimate how many US dollars could be sent with NZ$350. $ __________
Task administration: 
This task is completed with pencil and paper only.
Levels:
4, 5
Curriculum info: 
Maths, Number and Algebra, Patterns and relationships
Keywords: 
number patterns, linear equations, functional rules, graph construction
Description of task: 
Students complete a table and a rule for a linear equation for a foreign currency exchange. The values are then plotted and interpreted.
Learning Progression Frameworks
This resource can provide evidence of learning associated with
Patterns and relationships, sets 5-6
Patterns and relationships, sets 6-7
within the Mathematics Learning Progressions Frameworks.
Read more about the Learning Progressions Frameworks.
Answers/responses: 
 

Y10 (10/1998)
a) 260, 340, 420 easy
b) 2, add 20 easy
c) Graph accurately completed based on data given in a). easy
d) Accept range $161-$170. moderate
Diagnostic and formative information: 
  Student response Likely calculation Likely misconception
d) 720 350 × 2 + 20 Converts $US350 to $NZ rather than $NZ350 to $US.