2024 AMC 10B Problems/Problem 21
Contents
[hide]Problem
Two straight pipes (circular cylinders), with radii and , lie parallel and in contact on a flat floor. The figure below shows a head-on view. What is the sum of the possible radii of a third parallel pipe lying on the same floor and in contact with both?
Solution 1
In general, let the left and right outer circles and the center circle have radii . When three circles are tangent as described in the problem, we can deduce by Pythagorean theorem.
Setting we have , and setting we have . Thus our answer is .
~Mintylemon66
Video Solution 1 by Pi Academy (In Less Than 5 Mins ⚡🚀)
https://youtu.be/5fID8UOohr0?feature=shared
~ Pi Academy
See also
2024 AMC 10B (Problems • Answer Key • Resources) | ||
Preceded by Problem 20 |
Followed by Problem 22 | |
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 |
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