Question

1. A windshield wiper blade is 18 in Long. Calculate the area covered by the blade as it rotates through an angle of 122 degrees. Use 3.14 for pi. Round your answer to the nearest Square inch.
2. A spray irrigation system waters a section of a farmer's field. If the water shoots a distance of 75, what is the area that is watered as the sprinkler of 80 degrees? Use 3.14 for pi. Round your answer to the nearest square foot.

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Answer 1

1. Area of a circle is pi x R^2

Area = 3.14 x 18^2

Area = 3.14 x 324= 1017.36 sq. In.

The blade covers 122 out of 360 degrees.

1017.36 x 122/360 = 345 square inches.

2.

Like above.

Area =3.14 x 75^2 = 17,662.5 square feet

17662.5 x 80/360 = 3,925 square feet.