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Consecutive Numbers

An investigation involving adding and subtracting sets of consecutive numbers. Lots to find out, lots to explore.

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14 Divisors

What is the smallest number with exactly 14 divisors?

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Summing Consecutive Numbers

Many numbers can be expressed as the sum of two or more consecutive integers. For example, 15=7+8 and 10=1+2+3+4. Can you say which numbers can be expressed in this way?

Tricky Customer

Stage: 3 Short Challenge Level: Challenge Level:1

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.
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