Q50 of 53 Page 15

A dart is thrown at a circular board which has regions marked for scoring. If the dart hits the region 1, the player gets 50 points and if it hits the region 2, the player gets 100 points. If the dart hits the board, find probability of the player getting 100 points.

Area of bigger circle = 3.14×50×50


= 7850


Area of smaller circle = 3.14×20×20


=1256


Now if the player wants to score 100 points in a single shot then he will have to hit inside the smaller circle


So P(scoring 100) =


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