Andrew M. answered • 10/03/15
Tutor
New to Wyzant
Mathematics - Algebra a Specialty / F.I.T. Grad - B.S. w/Honors
I also get 600 + 60π
The cylinder has surface are determined by
SA = 2πr2 + 2πrh
The surface area of the cube is 6s2 with s representing the length of a side
This leads us initially to SA of the cake = 2πr2 + 2πrh + 6s2
In this case though, since the bottom the cylinder is on the top of the cake
the circular area composing the bottom part of the cylinder is not included
in the surface area so we subtract πr2 Leaving
SA = πr2 + 2πrh + 6s2 for the cake
Note: the same amount of area is also covered on the top of the cube so
this same amount is subtracted from the equation again...
The final equation for the surface area of the cake is
SA = 2πrh + 6s2
Since the diameter of the cylinder is 6, then r = 3, h = 10, s = 10
SA = 2π(3)(10) + 6(10)2
= 60π + 600
Michael J.
Actually Arnold, many tutors who have posted their answers on the Forum also provided some degree of explanation, whether they may be short or elaborate. But if you only post the answer, then other students reading the question beside the one who posted the question, and have a similar problem, may not understand how the solution was obtained.
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10/03/15
Arnold F.
I agree with what you are saying and usually I post the steps in full or give enough info so that (hopefully) the student would be able to finish it. This was just an "experiment" on my part to see if there was interest in how to do the problem from the student who actually posted it.
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10/03/15
Michael J.
I see where you are coming from. Experimenting is part of the learning process after all. It helps to understand a theory one might have, and hope to get the results one desires from that experiment with minimal error.
Some students need extra guidance to get the solution, whereas the others just need a verification of the solution. It depends on the situation.
May you have fun engaging in this forum.
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10/03/15
Arnold F.
10/03/15