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The homework grader is wrong?
The homework grader is wrong?
For one of my questions "Suppose we have ball with radius 6. Suppose you cut the ball in half. What is the volume of the half ball? Use 3.14 for pi and round your answer to the nearest tenth if necessary. The grader said I was wrong with the answer of 452.2, but then provided me with this solution:
First note that the full ball has volume
43π×63=228π.43π×63=228π.
The half-ball has half the volume of the full ball, so the volume is228π÷2=114π≈358.228π÷2=114π≈358.
The correct answer is: 358
That clearly cannot be correct because 6^3 is 216
216(4/3) = 288
and 288/2 = 144
so the answer should be 144(3.14) = 452.16 rounded up to 452.2 right?
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