Difference between revisions of "2021 AMC 12A Problems/Problem 24"

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==Problem==
 
==Problem==
These problems will not be posted until the 2021 AMC12A is released on Thursday, February 4, 2021.
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Semicircle <math>\Gamma</math> has diameter <math>\overline{AB}</math> of length <math>14</math>. Circle <math>\Omega</math> lies tangent to <math>\overline{AB}</math> and intersects <math>\Gamma</math> at points <math>Q</math> and <math>R</math>. If <math>QR=3\sqrt{3}</math> and <math>\angle QPR = 60^{\circ}</math>, then the area of <math>\triangle PQR</math> equals <math>\tfrac{a\sqrt{b}}{c}</math>, where <math>a</math> and <math>c</math> are relatively prime positive integers, and <math>b</math> is a positive integer not divisible by the square of any prime. What is <math>a+b+c</math>?
==Solution==
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The solutions will be posted once the problems are posted.
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<math>\textbf{(A) } 110\qquad\textbf{(B) } 114\qquad\textbf{(C) } 118\qquad\textbf{(D) } 122\qquad\textbf{(E) } 126\qquad</math>
==Note==
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See [[2021 AMC 12A Problems/Problem 1|problem 1]].
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==Video Solution by Punxsutawney Phil==
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https://youtube.com/watch?v=cEHF5iWMe9c
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==See also==
 
==See also==
 
{{AMC12 box|year=2021|ab=A|num-b=23|num-a=25}}
 
{{AMC12 box|year=2021|ab=A|num-b=23|num-a=25}}
 
{{MAA Notice}}
 
{{MAA Notice}}

Revision as of 13:11, 11 February 2021

Problem

Semicircle $\Gamma$ has diameter $\overline{AB}$ of length $14$. Circle $\Omega$ lies tangent to $\overline{AB}$ and intersects $\Gamma$ at points $Q$ and $R$. If $QR=3\sqrt{3}$ and $\angle QPR = 60^{\circ}$, then the area of $\triangle PQR$ equals $\tfrac{a\sqrt{b}}{c}$, where $a$ and $c$ are relatively prime positive integers, and $b$ is a positive integer not divisible by the square of any prime. What is $a+b+c$?

$\textbf{(A) } 110\qquad\textbf{(B) } 114\qquad\textbf{(C) } 118\qquad\textbf{(D) } 122\qquad\textbf{(E) } 126\qquad$

Video Solution by Punxsutawney Phil

https://youtube.com/watch?v=cEHF5iWMe9c

See also

2021 AMC 12A (ProblemsAnswer KeyResources)
Preceded by
Problem 23
Followed by
Problem 25
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 12 Problems and Solutions

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