Question 874133: what is the ratio for the volumes of two similar pyramids, given that the ratio of their edge lengths is 6.5?
-possible answers
a.25:36
b.216:125
c.36:25
d.125:216
Answer by KMST(5328)   (Show Source):
You can put this solution on YOUR website! I think there is a typo (not necessarily your fault).
THE THEORY:
When figures (2-D, on a plane), or solids (3-D) are similar (same shape, maybe scaled up, or down).
The ratios of corresponding length measures (diameter, edge, height, etc) are the same "scaling factor";
the ratios of corresponding surface area measures are the squares of the "scaling factor,"
and the ratios of corresponding volume measures are the cube of that "scaling factor."
THE PROBLEM AS POSTED:
The way you posted it, in this problem the scaling factor is  ,
meaning that all the lengths (base edges, other edges, height, etc) on one pyramid are times greater than the same length on the other pyramid.
The volume of the larger pyramid will be
 times larger than the volume of the smaller pyramid.
WHAT IT SHOULD HAVE BEEN:
However, if the ratio of edge lengths was  ,
the ratio of volumes would be
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