Question 7
Answer all ten questions and show detailed solutions. Printed time 60 minutes; each question 4 points. Subcriterion allocations are editorial.
Color the twelve small squares in the L-shaped diagram using three colors, so that:
(a) Squares sharing an edge have different colors.
(b) Each color is used in exactly four squares.
(c) Every 2 × 2 block of four small squares contained in the diagram uses all three colors.
Do not mix colors or use different colors in one square. Use B,G,R for the three colors. Show your detailed solution as instructed on the cover.
Color the twelve small squares in the L-shaped diagram using three colors, so that:
(a) Squares sharing an edge have different colors.
(b) Each color is used in exactly four squares.
(c) Every 2 × 2 block of four small squares contained in the diagram uses all three colors.
Do not mix colors or use different colors in one square. Use B,G,R for the three colors. Show your detailed solution as instructed on the cover.