lunes, 21 de febrero de 2011


How can you time a period of 9 minutes, using two sand clocks, one of 4 minutes and one of 7?

1 comentario:

  1. We try it and we decyphering the problem. I wrote our resolving solution on Project Diary in TwinSpace. It is not easy, it used our thinking logic, our knowledge, a pleasant time for beeing ambitious.
    For other puzzles and games we have to do it as pleasant "home work".
    Thank you