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# Cylinder Scatterplot

1. This is a really cool question.

2. Gregory Taylor says he doesn’t know what the kid was thinking. Thoughts?

## 3 replies on “Cylinder Scatterplot”

My guess is that Stu was disregarding the labels of “radius” and “height” on the axes. I’d say that the point represents how long the cylinder is, and that the position indicates whether it’s oriented horizontally or vertically.

But you’d have to ask Stu to know for sure.

I would have to agree. The other possibility for the student getting that idea, in my opinion, is due to the example to the right of the question. It simply says A: (insert cylinder), with the A: at the top of the cylinder, therefore for a student in a hurry (why are they always in such a hurry with maths questions?? Slow down guys, read, think, read again and think some more!) B is the bottom of the cylinder and the graph is just a representation of the length of the cylinder. Obviously this is incorrect when you read the graph labels, but for a student who is reading the question and (possibly) grasping for meaning, an idea hits and it is easy to ignore the “minor details” that don’t fit. I’d consider changing the example to explicitly say something like “If the cylinder corresponding to point A looks like this (see picture) what would the cylinder for point B look like?”

I don’t think it’s anything deeper than “A is at the top so B is at the bottom”. Perceiving A and B as points on the same cylinder, with B lower and further to the right?

I wonder if some different cues in the wording of the question would have gotten a different result, or something like “Cylinder A” as the caption under the given cylinder and “Cylinder B” under some blank space.