COMB . HENRY TAKES A 200 × 200 GRID OF UNIT SQUARES, AND CHOOSES•...

100 -comb . Henry takes a 200 × 200 grid of unit squares, and chooses

• Complete the cover sheet provided and attach it to

k of these squares and colours them so that James is unable to choose

the front of your script, followed by your solutions

150 uncoloured squares which form a 100-comb. What is the smallest

in question number order.

possible value of k?

• Staple all the pages neatly together in the top left

hand corner.