document.write( "Question 316472: A target consists of concentric circles of radii 1 cm, 2 cm and 3 cm. The innermost circle is colored red, the middle ring is colored white, and the outer ring is colored blue. If a point is chosen at random on the target, what is the probability that it lies in the blue region? Express your answer as a common fraction. \n" ); document.write( "

Algebra.Com's Answer #226398 by Fombitz(32388) $\"\"$ $\"About$

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\n" ); document.write( "Calculate the areas of each region.
\n" ); document.write( "The total target area is,
\n" ); document.write( " $\"Atot=pi%2A3%5E2=9%2Api\"$
\n" ); document.write( " $\"Ar=pi%2A1%5E2=pi\"$
\n" ); document.write( " $\"Aw=pi%2A2%5E2-pi%2A1%5E2=%284-1%29%2Api=3%2Api\"$
\n" ); document.write( " $\"Ab=pi%2A3%5E2-pi%2A2%5E2=%289-4%29%2Api=5%2Api\"$
\n" ); document.write( "The probabilities for each color is determined by the amount of area in each region compared to the total area.
\n" ); document.write( " $\"P%28R%29=%28pi%29%2F%289%2Api%29=1%2F9\"$
\n" ); document.write( " $\"P%28W%29=%283%2Api%29%2F%289%2Api%29=3%2F9=1%2F3\"$
\n" ); document.write( " $\"P%28B%29=%285%2Api%29%2F%289%2Api%29=5%2F9\"$
\n" ); document.write( "So, the probability of a blue region pick is 5/9. \n" ); document.write( "

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