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Weekly Problem 45 - 2013

Stage: 2 and 3 Challenge Level: Challenge Level:1

Which of the following numbers is the product of exactly $3$ distinct prime numbers?

$45$; $60$; $91$; $105$; $330$

 

If you liked this problem, here is an NRICH task which challenges you to use similar mathematical ideas.  


This problem is taken from the UKMT Mathematical Challenges.

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