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2018 AMC 12B Question 25

AMC12 · 2018 AMC 12B

Question 25

Circles $\omega_1,$ $\omega_2,$ and $\omega_3$ each have radius $4$ and are placed in the plane so that each circle is externally tangent to the other two. Points $P_1,$ $P_2,$ and $P_3$ lie on $\omega_1,$ $\omega_2,$ and $\omega_3,$ respectively, so that $P_1P_2=P_2P_3=P_3P_1$ and line $P_iP_{i+1}$ is tangent to $\omega_i$ for each $i=1,$ $2,$ $3,$ where $P_4=P_1.$ See the figure below. The area of $\triangle P_1P_2P_3$ can be written in the form $\sqrt{a}+\sqrt{b},$ where $a$ and $b$ are positive integers. What is $a+b?$

Question illustration
  1. $546$
  2. $548$
  3. $550$
  4. $552$
  5. $554$