Stage: 3 Challenge Level: 
A 3 digit number is multiplied by a 2 digit number and the calculation is written out as shown below.
Each star like this stands for one digit.
Apart from the zero shown the only digits which occur are 2,
3, 5 and 7. This is sufficient information to complete the whole
multiplication sum.
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This is sufficient information to complete the whole
multiplication sum.
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You might find this
sheet useful for working on the problem,
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Multiplication & division. Trial and improvement. Powers & roots. Properties of numbers. Interactivities. Addition & subtraction. Algorithms. Working systematically. Factors and multiples. Divisibility.
Published March 1999.
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