Stage: 3 Challenge Level: 
A number N is divisible by 10, 90, 98 and 882 but it is NOT divisible by 50 or 270 or 686 or 1764.
It is also known that N is a factor of 9261000.
What is N?
Divisibility. Modulus arithmetic. Common factors. smartphone. Properties of numbers. Prime factors. Working systematically. Factors and multiples. Multiplication & division. Workshop.
Published February 1999.
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