Fair Exchange
Identify the value of coins and notes to $5.
Devise and use problem solving strategies to explore situations mathematically
This problem shows a knowledge of both coins and what three whole numbers add to 5. It can also be solved using play money.
The Problem
Emma had a $5 note. She exchanged it with her brother Sam for three coins. What were the three coins?
Teaching Sequence
- Play "guess the coin" giving clues on its size, its picture, colour etc.
- Pose the problem to the class.
- As the students work, either individually or with a partner, ask them questions that focus their thinking on the coins.
Which coin has the largest value?
What could you buy with this coin?
Can you tell me what is on the other side of this coin? - Share solutions.
Extension to the problem
Emma exchanged the $5 note for 5 coins. What could they be?
Solution
The three coins are two $2 coins and a $1 coin.
Solution to the Extension:
(five $1) ($2, $1, $1, 50c, 50c)
| Attachment | Size |
|---|---|
| FairExchange.pdf | 52.96 KB |
| FairExchangeMaori.pdf | 61.11 KB |
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