The nine note problem to help you
"think out of the box"

At the right are nine dots arranged in a set of three rows. Your challenge is to draw four straight lines, which go through the middle of all of the dots without taking the pencil off the paper. If you were using a pencil, you must start from any position and draw the lines one after the other without taking your pencil off the page. Each line starts where the last line finishes.

Try this now by drawing nine dots on a piece of paper and try it with a pencil. Place your pencil somewhere, draw four straight lines without taking your pencil off the page. Each line must start where the last line finished.

See if you can find a solution. Do not look at the answer until you have either given up or found a solution on your own. Do not give up too easily!