Shapes on the Playground

Sally and Ben went outside the school to draw some very large shapes on the tarmac. None of the shapes they drew shared any sides with any other shape - they were all drawn separately although some small shapes were inside larger shapes. The children each had a box of ten sticks of chalk. Each stick drew $10$ metres before it was quite worn away. They both drew shapes with all sides one metre long.

Sally drew squares and octagons, sixteen shapes altogether, and used up all her chalk.

How many of each shape did she draw?

Ben drew triangles, hexagons and squares. He drew $20$ shapes and still had two sticks of chalk left. How many of each shape did he draw?