Weekly puzzle 3 – solution
Light Switches
Luckily for you, one trip is all that is needed.
Turn two switches to the “ON” position. Wait a few minutes. Turn off one of the two switches. When you reach the three lamps on the top floor, one light will be on, one light will be off and cool, one light will be off, but still warm.
Well done to Nancy Pickston who correctly solved this puzzle first and to all the people who emailed and commented. Puzzle 4 on Wed.

