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2011-02-01T00:00:01
<?xml version="1.0" encoding="UTF-8"?>
<mdoxml version="1.0"><br></br>
<p>We have exactly $100$ coins. There are five different values of
coins.</p>
<p>We have decided to buy a piece of computer software for $39.75$.
We have the correct money, not a penny more, not a penny less!</p>
<p>Can you discover what the five different types of coins are
worth and how many of each we have saved?</p>
<p><mdo:image alt="Some coins." src="pic9.gif"></mdo:image></p>
<br></br></mdoxml>
<mdoxml version="1.0"><p>Thank you for working out the money in our birthday present pot! We have had lots of suggestions from St Aldhelms School. Can they all be right?</p>
<p><strong>Matthew:</strong></p>
<table cellpadding="4" cellspacing="0">
<tbody>
<tr>
<td>20 * £1.00</td>
<td>=</td>
<td>£20.00</td>
</tr>
<tr>
<td>20 * 50p</td>
<td>=</td>
<td>£10.00</td>
</tr>
<tr>
<td>44 * 20p</td>
<td>=</td>
<td>£8.80</td>
</tr>
<tr>
<td>3 * 10p</td>
<td>=</td>
<td>30p</td>
</tr>
<tr>
<td>13 * 5p</td>
<td>=</td>
<td>65p</td>
</tr>
<tr>
<td>Total</td>
<td> </td>
<td><strong>£39.75</strong></td>
</tr>
</tbody>
</table>
<p><strong>Justin:</strong></p>
<table cellpadding="4" cellspacing="0">
<tbody>
<tr>
<td>7 * £1.00</td>
<td>=</td>
<td>£7.00</td>
</tr>
<tr>
<td>48 * 50p</td>
<td>=</td>
<td>£24.00</td>
</tr>
<tr>
<td>43 * 20p</td>
<td>=</td>
<td>£8.60</td>
</tr>
<tr>
<td>1 * 10p</td>
<td>=</td>
<td>£0.10</td>
</tr>
<tr>
<td>1 * 5p</td>
<td>=</td>
<td>£0.05</td>
</tr>
<tr>
<td>Total</td>
<td> </td>
<td><strong>£39.75</strong></td>
</tr>
</tbody>
</table>
<p><strong>Emma:</strong></p>
<table cellpadding="4" cellspacing="0">
<tbody>
<tr>
<td>10 * £1.00</td>
<td>=</td>
<td>£10.00</td>
</tr>
<tr>
<td>50 * 50p</td>
<td>=</td>
<td>£25.00</td>
</tr>
<tr>
<td>10 * 20p</td>
<td>=</td>
<td>£2.00</td>
</tr>
<tr>
<td>25 * 10p</td>
<td>=</td>
<td>£2.50</td>
</tr>
<tr>
<td>5 * 5p</td>
<td>=</td>
<td>25p</td>
</tr>
<tr>
<td>Total</td>
<td> </td>
<td><strong>£39.75</strong></td>
</tr>
</tbody>
</table>
<p>When you pay for things in shops you can give the money in lots of different ways but in this case you had a set number of coins, 100. are you surprised by the different answers?</p>
<p> </p></mdoxml>
<?xml version="1.0" encoding="UTF-8"?>
<mdoxml version="1.0"><br></br>
<p>We have the following numbers of the different value coins:</p>
<p>$46$, $23$, $14$, $10$ and $7$</p>
<p>But what are they?</p>
<p>All but one type of coin has a value that is a multiple of
five.</p>
<br></br></mdoxml>
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Thirty Nine, Seventy Five
We have exactly 100 coins. There are five different values of
coins. We have decided to buy a piece of computer software for
39.75. We have the correct money, not a penny more, not a penny
less! Can you discover what the five different types of coins are
worth and how many of each we have saved?
Measures and Mensuration
Money
Using, Applying and Reasoning about Mathematics
Mathematical reasoning & proof
Mathematics Tools
Coins