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Originally posted by lausey
Correct.

For example, for one sphere in a cube:

Volume of a sphere (radius r): (4 pi r^3) / 3

Volume of a cube (one side 2r): (2r)^3 = 8r^3

Ratio of cube wrt sphere = 8r^3 / [(4 pi r^3) / 3] = pi / 6 = 0.524 (to 3 sf)

r would cancel out regardless of the number of spheres so would also remain constant.

EDIT: specified 4 sf instead of 3 by mistake.
Oops, had one of my fractions the wrong way round:

Ratio of cube wrt sphere = [(4 pi r^3) / 3] / 8r^3 = pi / 6 = 0.524 (to 3 sf)

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thanks for all your help.
Since you're probably dying to know, I'll tell you how my exam went today.
Let's see... 5 big questions (all with abcd etc), 90 minutes to do it.
I start working, when the bell rings for the first time (after 45 minutes), I've completed questions 1-4 and am thinking "Jesus, I'll be finished in no time, only one more question to go... what am I gonna do with my remaining spare time?" Wrong. Very wrong indeed. I had 45 minutes to solve question five... and I couldn't do it. Gah I feel so stupid, especially since it wasn't a very hard question. But oh well. Hopefully there weren't too many points for that 😕
I'll let you know what my grade was when I get it back.
Thanks again for helping me out though 😉

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Originally posted by angie88
thanks for all your help.
Since you're probably dying to know, I'll tell you how my exam went today.
Let's see... 5 big questions (all with abcd etc), 90 minutes to do it.
I start working, when the bell rings for the first time (after 45 minutes), I've completed questions 1-4 and am thinking "Jesus, I'll be finished in no time, only one more questio ...[text shortened]... ll let you know what my grade was when I get it back.
Thanks again for helping me out though 😉
Don't worry Angie,

4 out of five should be enough for a 4-😉

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Originally posted by angie88
thanks for all your help.
Since you're probably dying to know, I'll tell you how my exam went today.
Let's see... 5 big questions (all with abcd etc), 90 minutes to do it.
I start working, when the bell rings for the first time (after 45 minutes), I've completed questions 1-4 and am thinking "Jesus, I'll be finished in no time, only one more questio ...[text shortened]... ll let you know what my grade was when I get it back.
Thanks again for helping me out though 😉
Last engineering mechanics exam I sat, 6 questions in 3 hours. Each worth 10 marks.

10, 9, 9, 9, 9 and 2.5 (not in order) for the questions.

:-/

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Originally posted by XanthosNZ
Last engineering mechanics exam I sat, 6 questions in 3 hours. Each worth 10 marks.

10, 9, 9, 9, 9 and 2.5 (not in order) for the questions.

:-/
Whats that, ENGR102?