
Connect the nine dots on the left with 4 straight
lines without taking your pencil off the paper and without going over the
same line more than once. 

Now, after solving the above problem, try to connect the
16 dots on the left with 6 straight lines. Again do this without taking
your pencil off the paper and without going over the same line more than
once. 

Using straight lines draw a cross by connecting 12 dots so
that 5 dots are inside the cross and 8 dots are outside the cross. The cross
has to be symmetrical. 