Stage: 2 Challenge Level: 
There are a number of coins on a table.
One quarter of the coins show heads.
If I turn over two coins, then one third show heads. How many coins are there altogether?
Calculating with fractions. Trial and improvement. Addition & subtraction. Multiplication & division. Factors and multiples. Fractions. Generalising. Working systematically. Divisibility. Using symbols.
Published March 2002,April 2002.
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