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Age 11 to 14 Short
Challenge Level
Charlie wants to buy a new house but he doesn't like house numbers that are divisible by $3$ or by $5$.
If all the houses numbered between $100$ and $150$ inclusive are for sale, how many houses can he choose from?
If you liked this problem, here is an NRICH task that challenges you to use similar mathematical ideas.
This problem is taken from the UKMT Mathematical Challenges.
You can find more short problems, arranged by curriculum topic, in our short problems collection.
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NRICH is part of the family of activities in the Millennium Mathematics Project.
NRICH is part of the family of activities in the Millennium Mathematics Project.