## Exceedingly Lame Final Question

Not on my final, fortunately, but it came up in a discussion. Without seeing the question, see if you can answer it.

Find the volume of ……
A. 5 cm3
B. 10 cm3
C. 12 cm3
D. 12 cm2

(sigh)

### 10 Responses

1. Lemme guess: rectangular prism?

(I can create triangular prisms or rectangular pyramids with integer dimensions for two of those answers, so that can’t be it. I can create a tetrahedron with integer dimensions for all three of the volume answers, so that can’t be it either…)

2. I mean trying to guess the answer, not what the original question was.😉

3. C. Sigh.
It’s pretty funny, actually.

4. C

Writing good distractors is tough, but not that tough.

Today my seniors were upset that the choices on the multiple choice will include conceptual errors. They wanted the other choices to be things like zebra, apple, or UFO. On a math test.

5. And what if the man who set this question thought “Well, they will be guessing… Let make one of the answers _look_ probable… And the right one is of course 5 cm^3…”
You must admit that this is possible (and rather smart, I guess;))

6. I missed this, I think.

I wanted to go for $12cm^3$, but no. Why would 5, 10, and 12 be possible numeric values? One is a sum, one is a product, one is a goof.

What is the volume of a rectangular prism with a square base, 1 cm on each side, and a height of 10 cm?

We have $10 \times 1 \times 1$ or $10 + 1 + 1$ or for a goof $10 \div (1 + 1)$

How’d I do?

7. You were one of those kids in high school who when they showed you one of those “find the next term in the pattern” puzzles found something different than just adding two, aren’t you?

8. Yes, but….

Doesn’t that make sense? If it was 12x1x1 or 6x2x1 or 4x3x1 o3 3x2x2, then 10 and 5 would be lousy distractors, right?

9. It does!

Unfortunately, the person who wrote the test wasn’t able to think that far.

10. […] Exceedingly Lame Final Question and Counterexamples (The Number Warrior) […]