Arc length and the area of a sector

Answer Key - Grade 10 Math Worksheet - Building Confidence

Circle the best answer, or write your answer on the line.

1. 1.

   Jun measures the crust of one slice of a round pizza. Circle O has radius 6 cm, and ∠COD = 60°. How long is arc CD in cm, in terms of π?

   2π
2. 2.

   Luz pipes icing along part of the edge of a round cookie. Circle O has radius 4 cm, and ∠COD = 135°. How long is arc CD in cm, in terms of π?

   3π
3. 3.

   Milo glues ribbon along part of the rim of a drum. Circle O has radius 10 cm, and ∠COD = 72°. How long is arc CD in cm, in terms of π?

   4π
4. 4.

   Noah saves a quarter of a round pizza for later. Circle O has radius 6 in.; sector COD has a 90° angle. What is its area in square inches, in terms of π?

   9π
5. 5.

   Pia covers one wedge of a round plate with a sticker. Circle O has radius 3 in.; sector COD has a 120° angle. What is its area in square inches, in terms of π?

   3π
6. 6.

   Ren paints one thin wedge on a round rug. Circle O has radius 8 in.; sector COD has a 45° angle. What is its area in square inches, in terms of π?

   8π
7. 7.

   Tala frosts the top of one wedge of a round cake. Circle O has radius 10 in.; sector COD has a 36° angle. What is its area in square inches, in terms of π?

   10π
8. 8.

   Zee takes a thin slice of a round pizza. Sector COD of circle O has a 40° angle. What fraction of the circle's area is sector COD?

   1/9
9. 9.

   Ari colors the biggest section of a spinner. Sector COD of circle O has a 150° angle. What fraction of the circle's area is sector COD?

   5/12
10. 10.

    Esme shades a clock face from 12 all the way round to 9. Sector COD of circle O has a 270° angle. What fraction of the circle's area is sector COD?

    3/4