Creating Diagrams to Represent Ratios
Kate and Christopher create a diagram to explain why the distance and times values for two cars make them go the same speed. In the process, they form a ratio by joining the distance and time values for one car into a unit or “little trip,” which can be repeated (iterated) or split apart (partitioned) to solve proportional reasoning problems.
Episode 1: Making Sense
Kate and Christopher notice two patterns in the distance and time values for cars that are going the same speed.
Episode 2: Making Sense
The students continue to suggest and test patterns. They are surprised that some patterns do not work.
Episode 3: Exploring
Christopher and Kate create a diagram to explain why a car traveling 20 miles in 8 minutes goes the same speed as a car traveling 10 miles in 4 minutes.
Episode 4: Repeating Your Reasoning
Kate and Christopher draw a diagram to show why traveling 15 miles in 6 minutes is the same speed as going 10 miles in 4 minutes.