Place four pebbles on the sand in the form of a square. Keep adding
as few pebbles as necessary to double the area. How many extra
pebbles are added each time?
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!
For this challenge, you'll need to play Got It! Can you explain the
strategy for winning this game with any target?
How many integers between 1 and 1200 are NOT
multiples of any of the numbers 2, 3 or 5?
Working along the same lines, Emma and Laura from The Mount School,
York sent the diagramand Lorn from Stamford School sent
the solution below:
Lorn found another method, using similar
ideas, sparked from the Venn diagram shown in the original
Venn diagram showing whole numbers from 1 to
Congratulations for your work on this
problem to Samantha of Hethersett High School, Norfolk, Jenny,
Caroline, Emma, Rachel and Beth from the Mount School, York and to