This applet is suitable for demonstrating the arithmetic of problems on Ratio Rate and Direct Proportion.
The 2nd window below with input boxes allows the user/learner to change the quantities.
The bar model size and location may also be adjusted to fit the window by using the sliders barwidth, spacer, and scalefactor.
A clear and visual understanding of the concept and procedure of dividing and multiplying one quantity and the other simultaneously by the same factors appropriately to obtain answers to such problems is key to easily compute/solve such problems.
