Place 9 balls ("o") in the intersections of the grid below to achieve 10 straight lines, each line containing 3 and exactly 3 balls. You may assume, if you need, that each cell is a perfect square.

           +---+---+---+---+---+---+---+---+
           |   |   |   |   |   |   |   |   |
           +---+---+---+---+---+---+---+---+
           |   |   |   |   |   |   |   |   |
           +---+---+---+---+---+---+---+---+
           |   |   |   |   |   |   |   |   |
           +---+---+---+---+---+---+---+---+
           |   |   |   |   |   |   |   |   |
           +---+---+---+---+---+---+---+---+
           |   |   |   |   |   |   |   |   |
           +---+---+---+---+---+---+---+---+
           |   |   |   |   |   |   |   |   |
           +---+---+---+---+---+---+---+---+

(In reply to Thanks for another good puzzle by Leming)

Very kind of you, Leming.

"Nescire inepto res ineptior nulla est."

Cheers.

Posted by pcbouhid on 2008-10-15 21:01:35