In the green rectangular board of measure 20×15 ,there is a white square with side 10 units. In the square, there is a orange right angle triangle of measure 3×4×5 . Find the probability that a dart strikes in orange portion
Area of the (orange) right triangle
=(3*4)/2
=6 units
Area of the rectangular board
=20*15
=300 units
Assume that
1. a dart always falls within the rectangular board
2. the probability of hitting anywhere in the rectangle is equal
then the probability of the dart striking the orange portion is 6/300=1/50