CPM Homework Help : A2C Problem 9-96

In one of the games at the county fair, people pay to shoot a paint pistol at the target shown below right. The center has a radius of one inch. Each concentric circle has a radius one inch larger than the preceding circle. Assuming the paint pellet hits the target randomly, what is the probability that it hits: Homework Help ✎
1. The 50-point ring?
2. The 20-point ring?

Hint (a):

Area of a circle = πr²

More Help (a):

$P(50pt)=\frac{\text{area of success}}{\text{total area}}=\frac{\pi(1)^{2}}{\pi(4)^{2}}$

Answer (a):

$\frac{1}{16}$

Hint (b):

$P(20pt)=\frac{\text{area of success}}{\text{total area}}=\frac{\pi(2)^{2}-\pi(1)^{2}}{\pi(4)^{2}}$