Damien wishes to find out if 457 is a prime number. In order to do this he needs to check whether it is exactly divisible by some prime numbers. What is the smallest number of possible prime number divisors that Damien needs to check before he can be sure that 457 is a prime number?
Select one option, then click Submit.
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Select an option, then submit.
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Senior Mathematical Challenge 2007 (2007)
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