Google Classroom
GeoGebraAula GeoGebra

lick of paint - Team A

Max can contribute another find from the cellar - blue paint that his grandpa had filled into an old vessel. The strange shape of the vessel makes it quite difficult to estimate the amount of paint inside.
Vessel with paint
Vessel with paint
Sarah and Max would like to be able to estimate whether enough paint is left to paint the rest of the treehouse after they are finished with the front wall (including door). And again they would like to know if enough is left after completing front wall and both side walls. The front wall is of the same size as the back wall and as both side walls together. Estimate: What is the fill height in the vessel when one third, or two third respectively have been used? Sketch these fill heights in the following simulation "Fill Height" by using the Pen-Tool Toolbar Image, that can be found in the pull down menue which appears when clicking on the arrow Toolbar Image.

Fill Height

Now Max and Sarah can estimate if the remaining paint will suffice. But it might be more usefull to know this beforehand would be even better! You can help with the simulation Vessel.

Vessel

Click on the button "+20 ml" in the simulation to fill 20 ml into the vessel. Observe the fill height in the vessel. Repeat filling the vessel with 20 ml until it is full. Write down your first observations.

How much colour fits into the vessel in total?

Now click on "Gefäß leeren" to empty the vessel. Fill it up to one third with paint by clicking repeatedly. Then fill it up to two third. Compare the two fill heights in the simulation with your estimations from tast No. 34. How well did you do?

Marqueu on calgui
  • A
  • B
  • C
  • D
Comprova la meva reposta (3)

If you were successfull, reveal to Sarah and Max how you did it. If your guess was not very accurate, try to find out why and describe what went wrong.

Great! The vessel in the simulation is of the same shape as Grandpa's vessel of paint - but the latter fits double the amount of paint.

Now you can calculate for Sarah and Max whether the amount of paint will suffice. 100 ml paint is needed per squaremeter. The side walls are rectangular, 1,50 m broad and 2 m high. Make notes of your calculations. (what you know: front and back wall have the same size. Both side walls together have the same size as well.)