1 of 84 shape and space circles. 2 of 84 the circumference of a circle use π = 3.14 to find the...
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SHAPE AND SPACE
Circles
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The circumference of a circle
Use π = 3.14 to find the circumference of this circle.
C = πd8 cm
= 3.14 × 8
= 25.12 cm
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The circumference of a circle Use π = 3.14 to find the circumference of the
following circles:
C = πd4 cm
= 3.14 × 4
= 12.56 cm
C = 2πr9 m
= 2 × 3.14 × 9
= 56.52 m
C = πd
23 mm = 3.14 × 23
= 72.22 mm
C = 2πr58 cm
= 2 × 3.14 × 58
= 364.24 cm
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Formula for the area of a circle
We can find the area of a circle using the formula
radius
Area of a circle = πr2
Area of a circle = π × r × ror
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The circumference of a circle
Use π = 3.14 to find the area of this circle.
A = πr2
4 cm = 3.14 × 4 × 4
= 50.24 cm2
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The area of a circle Use π = 3.14 to find the area of the following circles:
A = πr22 cm
= 3.14 × 22
= 12.56 cm2
A = πr210 m
= 3.14 × 52
= 78.5 m2
A = πr2
23 mm = 3.14 × 232
= 1661.06 mm2
A = πr278 cm
= 3.14 × 392
= 4775.94 cm2
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Practice Time!
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