### 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?

# Weekly Problem 12 - 2010

##### Stage: 2 and 3 Short Challenge Level:

After her second test her average mark is $\frac{6}{10}$, after her third test her average is $\frac{11}{15}$, after her fourth it is $\frac{16}{20}=\frac{4}{5}=80$% exactly and after the fifth it is $\frac{21}{25}=84$%.

So she needs to take four more tests to obtain an average mark of more than $80$%.

This problem is taken from the UKMT Mathematical Challenges.

View the previous week's solution
View the current weekly problem