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?
Arrange your fences to make the largest rectangular space you can. Try with four fences, then five, then six etc.
An activity making various patterns with 2 x 1 rectangular tiles.
Sammy and George from Ardingly, and Bilge, age 12 all sent in correct answers to the first part of the question.
As George explains:
The fault-free rectangle looks like this:
Congratulations to V. Abhijit, age 15 who sent in a fuller solution:
V. Abhijit goes on to generalise...
V. Abhijit gives the smallest fault-free rectangle that can be made using 2 by 1 rectangles as that shown below:
Can you find another?