Circle Area Circumference Demonstration This resource provides animated

Circle – Area & Circumference – Demonstration This resource provides animated demonstrations of the mathematical method. Check animations and delete slides not needed for your class.

A circle is a shape where all points are equidistant from a centre. The area of a circle is the space within the circle. The perimeter of a circle is called the circumference. Centre Diameter Circumference 4 cm Radius

Circumference = 3…. . × Diameter What is the relationship Di am × Diameter between a circle’s Circumference = 3. 1415926535… et er circumference and its diameter? Circumference Diameter 1 Diameter 2 Diameter 3 3. 14

Di am et er Circumference Diameter 1 Diameter 2 Diameter 3 3. 14

DEMO Circumference of Circles Find the circumference of this circle. (to 1 dp) 5 cm cm

DEMO Circumference of Circles Find the circumference of this circle. (to 1 dp) 8 mm mm

DEMO Circumference of Circles Find the circumference of this circle. (to 1 dp) 6 cm cm

DEMO Circumference of Circles Find the circumference of this circle. (to 1 dp) 8 m m

DEMO YOUR TURN Circumference of Circles Find the circumference of this circle. (to 1 dp) 8 m m Find the circumference of this circle. (to 1 dp) 7 mm mm

DEMO Circumference of Circles Find the circumference of this circle. (to 1 dp) 8 m m YOUR TURN Find the circumference of this circle. (to 1 dp) 12 cm

DEMO YOUR TURN Circumference of Circles Find the circumference of this circle. (to 1 dp) 8 m m Find the circumference of this circle. (to 1 dp) 9 mm mm

DEMO Circumference of Circles Find the circumference of this circle. (to 1 dp) YOUR TURN Find the circumference of this circle. (to 1 dp) 8 m 3 cm m cm

DEMO Circumference of Circles Find the circumference of this circle. (to 1 dp) 8 m m YOUR TURN Find the circumference of this circle. (to 1 dp) 10 m m

DEMO YOUR TURN Circumference of Circles Find the circumference of this circle. (to 1 dp) Find the diameter of this circle. (to 1 dp) 28 cm 8 m m cm

DEMO YOUR TURN Circumference of Circles Find the circumference of this circle. (to 1 dp) Find the circumference of these circles (to 1 dp) 12. 6 cm 4 cm 13 m 8 m 6 mm 18. 8 mm 40. 8 m 4 cm 50. 3 m m 8 m 53. 4 in 8. 5 in

Find the perimeter of these shapes. (1 dp) Find the radius of these shapes. 45 cm 9 cm 56. 5 cm 7. 2 cm 64 cm 12 cm 61. 7 cm 6 cm Not to scale. 21. 4 cm 33 cm 10. 5 cm 10. 2 cm

38 cm A car wheel has a radius of 38 cm. If it rolls 120 times, how far does it travel? 70 cm 28, 651. 3 cm = 286. 5 m A bicycle wheel has a 70 cm diameter. How many times would it rotate if the bicycle travelled 100 meters? 45. 47 times = 45 times A unicycle’s wheel has a radius of 28 cm. How many complete revolutions would it take a rider to travel 1. 3 km? 738. 9 times = 739 complete revolutions The unicycle’s pedal is 15 cm long. How far does the rider need to move their feet to travel 1. 3 km?

What is the height and base of this parallelogram? Height = radius Base = half the circumference

DEMO Area of Circles Find the area of this circle. (to 1 dp) 5 cm cm 2

DEMO Area of Circles Find the area of this circle. (to 1 dp) 12 mm mm 2

DEMO Area of Circles Find the area of this circle. (to 1 dp) 7 m m 2

DEMO Area of Circles Find the area of this circle. (to 1 dp) 4 cm cm 2

DEMO Area of Circles Find the area of this circle. (to 1 dp) YOUR TURN Find the area of this circle. (to 1 dp) 7 cm 4 cm cm 2

DEMO YOUR TURN Area of Circles Find the area of this circle. (to 1 dp) 4 cm Find the area of this circle. (to 1 dp) 9 mm cm 2 mm 2

DEMO YOUR TURN Area of Circles Find the area of this circle. (to 1 dp) 3. 8 m 4 cm cm 2

DEMO YOUR TURN Area of Circles Find the area of this circle. (to 1 dp) 15 cm 4 cm cm 2

DEMO YOUR TURN Area of Circles Find the area of this circle. (to 1 dp) Find the area of this shape. (to 1 dp) 11 cm 4 cm cm 2

DEMO YOUR TURN Area of Circles Find the area of this circle. (to 1 dp) Find the radius of this circle. (to 1 dp) 65 cm 2 4 cm cm 2 cm

DEMO YOUR TURN Area of Circles Find the area of this circle. (to 1 dp) Find the area of these circles. (to 1 dp) 28. 3 cm 2 78. 5 cm 2 3 cm 5 cm 4 cm 14 mm 153. 9 mm 2 cm 2 11 m 95. 0 m 2

Find the area of these shapes. (1 dp) 19 cm 283. 5 cm 2 3 cm 5 cm 75. 4 cm 2 66. 4 cm 2 117. 8 cm 2 6 cm 13 cm 28. 3 cm 2 Not to scale. 15 cm

DEMO Area & Circumference of Circles Find the area & circumference of this circle. (to 1 dp) 12 m

DEMO Area & Circumference of Circles Find the area & circumference of this circle. (to 1 dp) 20 cm

DEMO Area & Circumference of Circles Find the area & circumference of this circle. (to 1 dp) 3 m

DEMO Area & Circumference of Circles Find the area & circumference of this circle. (to 1 dp) 3 m 9 cm

DEMO Area & Circumference of Circles Find the area & circumference of this circle. (to 1 dp) 3 m 10 m

DEMO Area & Circumference of Circles Find the area & circumference of this circle. (to 1 dp) 15 cm 3 m

DEMO Area & Circumference of Circles Find the area & circumference of this circle. (to 1 dp) 3 m Find the area & circumference of these circles. (to 1 dp) 26 cm A = 530. 9 cm 2 C = 81. 7 cm 17 m A = 227. 0 m 2 C = 53. 4 m 6. 5 cm A = 132. 7 cm 2 C = 40. 8 cm A = 490. 9 mm 2 C = 78. 5 mm 25 mm

Find the area & perimeter of these shapes. (1 dp) 12 cm 8 cm 23 cm A = 415. 5 cm 2 P = 72. 3 cm A = 89. 1 cm 2 P = 36. 6 cm A = 25. 1 cm 2 P = 20. 6 cm 24 cm A = 153. 9 cm 2 P = 50. 0 cm 8 cm A = 218. 5 cm 2 P = 59. 4 cm Find the circumference of this circle. 13 cm 14 cm Not to scale. 10 cm 42 cm 2 23. 0 cm

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