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MATH / The dartboard below has a radius of 6 inches. Each of the concentric circles has…

Problem

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problem

The dartboard below has a radius of 6 inches. Each of the concentric circles has a radius two inches less than the next larger circle. If nine darts land randomly on the target, how many darts would we expect to land in a non-shaded region?

[asy]import graph;
fill(Circle((0,0),15),gray(0.7));
fill(Circle((0,0),10),white);
draw(Circle((0,0),20));
draw(Circle((0,0),15));
draw(Circle((0,0),10));
[/asy]

level

Level 3

type

Counting & Probability

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