Consecutive Numbers

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

14 Divisors

What is the smallest number with exactly 14 divisors?

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?

Stage: 2 and 3 Short Challenge Level:

Reading the digits from behind is the same as reflecting them in a vertical line of symmetry. This means $0$ and $8$ are read as themselves, and $2$ and $5$ are swapped. Note that the digits are read in the opposite order

Since the time is before $10:00$, the first hour digit must be a $0$. When read from behind, this means the last digit must also be a $0$. Since the time is between $3:00$ and $10:00$ and the second hour digit must be one that reads backwards as another digit, it must be either $5$ or $8$.

Since $08:80$ is not a valid time, the time must be $05:20$.

This problem is taken from the UKMT Mathematical Challenges.
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