Difference between revisions of "2018 AMC 10B Problems/Problem 10"
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==Solution 1== | ==Solution 1== | ||
− | Consider the cross-sectional plane | + | Consider the cross-sectional plane and label it b. Note that <math>bh/2=3</math> and we want <math>bh/3</math>, so the answer is <math>\boxed{2}</math>. (AOPS12142015) |
==Solution 2== | ==Solution 2== |
Revision as of 19:48, 17 February 2018
Contents
Problem
In the rectangular parallelpiped shown, =
,
=
, and
=
. Point
is the midpoint of
. What is the volume of the rectangular pyramid with base
and apex
?
Solution 1
Consider the cross-sectional plane and label it b. Note that and we want
, so the answer is
. (AOPS12142015)
Solution 2
IMPORTANT: This solution assumed that the parallelepiped is a rectangular prism, which isn't correct. All we know is that each side is a parallelogram, so this solution didn't work. Sorry Adarshk.
Solution 3
IMPORTANT: This solution assumed that the parallelepiped is a rectangular prism, which isn't correct. All we know is that each side is a parallelogram, so this solution didn't work. Sorry Archimedes15.
Solution 4 (Vectors)
IMPORTANT: This solution assumed that the parallelepiped is a rectangular prism, which isn't correct. All we know is that each side is a parallelogram, so this solution didn't work. Sorry SS4. .
Solution 5 (slicker method)
IMPORTANT: This solution assumed that the parallelepiped is a rectangular prism, which isn't correct. All we know is that each side is a parallelogram, so this solution didn't work. Sorry MathloverMC
See Also
2018 AMC 10B (Problems • Answer Key • Resources) | ||
Preceded by Problem 9 |
Followed by Problem 11 | |
1 • 2 • 3 • 4 • 5 • 6 • 7 • 8 • 9 • 10 • 11 • 12 • 13 • 14 • 15 • 16 • 17 • 18 • 19 • 20 • 21 • 22 • 23 • 24 • 25 | ||
All AMC 10 Problems and Solutions |
The problems on this page are copyrighted by the Mathematical Association of America's American Mathematics Competitions.