### Consecutive Numbers

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

### Calendar Capers

Choose any three by three square of dates on a calendar page...

Make a set of numbers that use all the digits from 1 to 9, once and once only. Add them up. The result is divisible by 9. Add each of the digits in the new number. What is their sum? Now try some other possibilities for yourself!

# Calculation 2000

##### Age 11 to 14 ShortChallenge Level

$$2000+1999\times2000=(1+1999) \times 2000= 2000 \times 2000 = 4 000 000$$