The dartboard above is made up of three concentric circles with radii 1, 3, and 5. Assuming that a dart thrown will land randomly on the dartboard, what is the probability that it lands in the green region?

Guest Dec 2, 2019

#1**0 **

Red area = pi x r^2 = pi (1^2) = pi

Green area = pi r^2 - the red area = 9 pi - pi = 8 pi

Blue area = pi r^2 - green - red areas = 25pi - 8pi - pi = 16 pi

Total area is pi r^2 = 25 pi (16pi + 8pi + pi)

green area is 8 pi

8pi/25pi = 8/25

ElectricPavlov Dec 3, 2019