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?
Using symbols. Odd and even numbers. Divisibility. Trial and improvement. Working systematically. Multiplication & division. Calculating with fractions. Factors and multiples. Addition & subtraction. Fractions.
Published March 2002,April 2002.
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