Ratio and proportion – match the target ratio

MathematicsAlgebraAges 11–12

Move two "hands" up and down two vertical bars so that the ratio of their heights equals the target ratio; the background colour changes continuously to show how close you are. The Discover screen offers preset target ratios (1 : 1 to 5 : 6); the Create screen lets students choose two numbers a and b as their own ratio and then try to match it. On a touch screen each hand can be dragged independently with its own finger. Adapted from the "Ratio and Proportion" simulation by PhET Interactive Simulations, University of Colorado Boulder (CC BY 4.0); rewritten.

Lesson: Ratios and percentages