Question

Khalil has a game board as shown below, which is a square with 20-cm sides. The area of the largest circle is 314 square centimeters.

3 concentric circles inside of a green square. The largest circle is labeled 1, the next circle is labeled 3, and the smallest circle is labeled 5.

What is the probability of scoring 1, 3, or 5 points with one randomly thrown dart?
50%
62.5%
75%
78.5%

Answer 1

Area of square = 20^2 = 400 cm^2. The largest circle’s area is 314 cm^2, and scoring 1, 3 or 5 requires the dart to land somewhere inside that circle.

Probability = area of circle / area of square = 314/400 = 0.785 = 78.5%.

Answer: 78.5%