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| sphere volume formula |
Kennan's displayed ignorance of mathematics before, so we weren't expecting a great deal from him... and he didn't disappoint. Oh, sure, he managed to (more or less) correctly define a sphere:
"A sphere is a three-dimensional, round object, such as a marble or soccer ball..."...and also cobbled together a wordy expression for the formula of a sphere's volume:
"The formula for the volume of a sphere is 4/3 times pi times the radius cubed."He did, however, blow it when he attempted to explain the meaning of "cubed" (which we suspect he only did to increase word count):
"Cubing a number means multiplying it by itself three times."We find that last ambiguous, at best; and, in reality, a condition many would call "wrong." Had that been his only crime against mathematics, we might have let Kennan slide. Where Mark got confused was in his assumption that the OQ wanted him to do all the work for a sphere with a radius of 19 units, but leave it with 9145.33π as the answer. Kennan's arithmetic is correct, even if his text is ponderous (that took him almost 110 words). The question, however, is whether that's what the OQ wanted to know.
| We think the OQ actually wanted to solve the equation
A = 4⁄3πr³
for π, not just perform two-thirds of the arithmetic operations. After all, that makes (a little) more sense, especially in beginning math class practice. In that case, some quick wrangling of the formula reveals that
π = A / (4⁄3*r³).
Based on that much more general solution, we hereby crown Mark Kennan (Michael Keenan) our Dumbass of the Day. |
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¹ We don't think that the name of a lower-case Greek letter (pi, for π) should have been capitalized in the title, but what do we know? None of us has a journalism degree...
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