Interpreting and comparing proportional relationships
About this video
A graph shows time (vertical axis) against distance (horizontal axis) for four wind-up toy robots. By picking one distance, 3 meters, and comparing how long each robot took, the video shows Camila's robot took the longest, so it is the slowest.
You'll be able to
- read a graph where time is on the vertical axis and distance on the horizontal axis.
- compare speeds by picking one distance and comparing the times.
- explain why the steepest line on a time-vs-distance graph is the slowest.
Key words
- constant speed
- Moving the same distance in each second, which shows up as a straight line on the graph.
- vertical axis
- The up-and-down axis of a graph; here it shows time in seconds.
- horizontal axis
- The left-to-right axis of a graph; here it shows distance in meters.
Transcript
- [Instructor] The graph shows the relationship between time and distance for four wind-up toy robots crossing a floor. Whose toy robot is the slowest? Pause this video and try to figure that out. Okay, let's do this together. So in the vertical axis, we have time in seconds.
So that's for, for example, this point right over here shows that Camila's robot, it took six seconds to go one meter. The horizontal axis is meter right over here. So for any given distance in the horizontal axis, we can figure out how long it took to travel that distance.
So one way to think about it is let's just pick a distance where we have a point for all of them. So let's say this distance of three meters. It took Darius's robot about a little over two seconds. It took Ben's robot a little over it looks like five seconds. It took Amira's robot looks like a little under nine seconds.
And it took Camila's robot looks like around 19 seconds. So it took Camila's robot the longest to travel those three meters, and they're all traveling at constant speeds. We can see that these are all straight lines over here. And so, for any distance that you pick, you see that Camila's robot is definitely taking the longest.
So Camila's robot is the slowest.
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