Question

Shown in the picture below are three concentric (having the same

center) circles. Let's name them small, larger and largest. You are
blindfolded and throwing a dart at the target. What is the probability
that the dart will hit the white area inside the circles ? The white area
is formed by the small circle and by the area between the larger and
largest circles that looks like a ring. Assume that the dart you throw,
will hit somewhere inside the largest circle.
Enter your answer as a decimal.

Answer 1

.68

Explanation:

The radius of the largest circle is: 2+1+2=5

The area of the largest circle :
`\pi (5)^(2)= 25` sq units

The radius of the larger circle is: 2+1=3

Area of the larger circle is:
`\pi (3)^(2)=9` sq units

The area of the smaller circle:
`\pi (1)^(2) = \pi`

`25\pi - 9\pi = 16\pi \\16\pi +1 \pi = 17\pi \\\\17 /25=.68`

DO NOT USE THE (pi) for the last step