two lap average [for teachers]
Andrei drives a 60 mile course in 1 hour. How fast does he have to drive a second lap in order to average 120 miles per hour for the two laps?
The left panel shows the given data in the {time, distance} plane.
The right panel shows the given data in the {time, speed} plane.
You can explore the problem by dragging the YELLOW DOT in the left hand panel.
- How are speeds represented in the left panel?
- How are distances represented in the right panel?
- Which representation do you think provides you with more insight? Why?
- How can you use this applet to generate more problems of this sort?
- What questions could/would you ask your students?
- What have you learned about word problems from this applet?