Difference between revisions of "2024 AMC 10B Problems/Problem 21"

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==Problem==
 
==Problem==
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Two straight pipes (circular cylinders), with radii <math>1</math> and <math>\frac{1}{4}</math>, 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?
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[asy]
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size(6cm);
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draw(circle((0,1),1), linewidth(1.2));
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draw((-1,0)--(1.25,0), linewidth(1.2));
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draw(circle((1,1/4),1/4), linewidth(1.2));
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[/asy]
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<math>\textbf{(A)}~\displaystyle\frac{1}{9}
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\qquad\textbf{(B)}~1
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\qquad\textbf{(C)}~\displaystyle\frac{10}{9}
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\qquad\textbf{(D)}~\displaystyle\frac{11}{9}
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\qquad\textbf{(E)}~\displaystyle\frac{19}{9}</math>
  
 
==Solution 1==
 
==Solution 1==

Revision as of 08:32, 14 November 2024

Problem

Two straight pipes (circular cylinders), with radii $1$ and $\frac{1}{4}$, 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?

[asy] size(6cm); draw(circle((0,1),1), linewidth(1.2)); draw((-1,0)--(1.25,0), linewidth(1.2)); draw(circle((1,1/4),1/4), linewidth(1.2)); [/asy]

$\textbf{(A)}~\displaystyle\frac{1}{9} \qquad\textbf{(B)}~1 \qquad\textbf{(C)}~\displaystyle\frac{10}{9} \qquad\textbf{(D)}~\displaystyle\frac{11}{9} \qquad\textbf{(E)}~\displaystyle\frac{19}{9}$

Solution 1

See also

2024 AMC 10B (ProblemsAnswer KeyResources)
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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