Grade 8 Problems and Questions on Circles with Answers

Circle problems and questions with answers for grade 8 are presented. These problems and questions deal with calculating circumference and area of circles. Also solutions and explanations are included.

  1. The three circles C1, C2 and C3 have their centers O1, O2 and O3 on the line L and are all tangent at the same point. If the diameter of the largest circle is 20 units, what is the ratio of the area of the largest circle to the area of the smallest circle?

    circles problem 1.

  2. Mrs Parkinson's garden is made up of 4 squares and 2 semicircles as shown below. Each small square has an area of 4 square meters. Find the total area of the garden.


  3. A water sprinkler can spray water at a maximum distance of 12 m in all directions. What area of the garden can this sprinkler irriguate? round your answer to the nearest square meter.

  4. A circular garden with a diameter of 10 meters is surrounded by a walkway of width 1 meter. Find the area of the walkway (shaded part).

    circles problem 4.

  5. A circular pizza costs $19.99. What is the cost of 1 square centimeter if the diameter of the pizza is 36 cm?

  6. How much fencing is needed for the Robinsons circular flower garden that has an area of 5 square meters?(round your answer to the nearest meter.)

  7. The radius of circular disk is increased by 20%. What is the percent increase in the area of the disk?

  8. A circular table has a dimeter of 100 inches. A circular tablecloth hangs over the table 15 inches around the table. What is the area of the tablecloth?

  9. ABCD is a square with one vertex at the center of the circle and two vertices on the circle. What is the length of AC if the area of the circle is 100 square cm?

    circles problem 9.

  10. The ratio of the perimeter of circle A to the perimeter of circle B is 3:1. What is the ratio of the area of circle A to the area of circle B?

Answers to the Above Questions

  1. 16
  2. 4 pi + 16 square units
  3. 452 square meters
  4. 21 pi square meters
  5. $0.02 per square centimeters
  6. length of fencing is 8 meters
  7. percentage change in area is 44%
  8. 13,273 square inches
  9. length of AC = 10 sqrt(2/pi)
  10. ratio of areas = 9:1

More References and Links

Middle School Math (Grades 6, 7, 8, 9) - Free Questions and Problems With Answers
High School Math (Grades 10, 11 and 12) - Free Questions and Problems With Answers
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