SAT TRIANGULAR PRISM PROBLEM

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Animated gif showing one way to "draw" the prism above

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SAT Geom questions often assess 3-D spatial visualization. Do you think your students will find the following trivial?

I'm still playing with my Handraw app so the diagrams will continue to be sloppy!

FIND THE VOLUME OF THE RIGHT ISOS TRIANGULAR RIGHT PRISM ABOVE.

Note: Markings are intended to indicate that the height of the prism equals the equal legs of the bases.

[NOTE: Error in labeling choices has been corrected.]

(A) 108 (B) 108√2  (C) 54√2 (D) 27√2 (E) (27√2)/2


Ans: D [Corrected]

How would you explain this?
What methods do you think students who solve this will use?
Apart from the poorly drawn diagram, how many students do you think would quickly recognize that the prism is half of a cube.





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