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MATH / A target consists of four concentric circles with radii 4 inches, 6 inches, 8…

Problem

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problem

A target consists of four concentric circles with radii 4 inches, 6 inches, 8 inches and 10 inches as shown. Given that a dart is thrown that hits the target at a random point, what is the probability that it hits a shaded region? Express your answer as a common fraction.

[asy]size(100); import graph; fill(Circle((0,0),5),gray(.6));

clip(Circle((0,0),2) ^^ Circle((0,0),3) ^^ Circle((0,0),4),fillrule(1));
draw(Circle((0,0),2) ^^ Circle((0,0),3) ^^ Circle((0,0),4) ^^ Circle((0,0),5));[/asy]

level

Level 3

type

Counting & Probability

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