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RectanglesPerimeter 15 m 5 m 15 m 5 m Perimeter =15 m+ 5 m+ 15 m+ 5 m= 40 m The perimeter of a shape is the distance around the outside. Length Width

P= 4 x 5 = 20 cm P= 5 x 6 = 30 cm P= 6 x 7 = 42 cm P= = 16 mm 5 cm Find the perimeter of the shapes below. Regular PentagonRegular Hexagon Regular Quadrilateral 6 cm 7 cm Irregular Quadrilateral 3 mm 4 mm 6 mm 3 mm 9 mm 7 mm 10 mm 3 mm Irregular Pentagon Diagrams not to scale P= = 32 mm Square

4m 3m Diagrams Not to scale Perimeter of Compound Shapes ? ? ? Perimeter = 4 m + 7 m +3m + 1m += 22m 4m 3m 1m

? ? Perimeter of Compound Shapes 8 m 2 m 5 m 2 m Not to scale Perimeter = 2 m + 5 m +4 m +2 m + 5 m +8 m = 30 m 4 m 5 m

The Circumference of a Circle Find the circumference of the following circles. C =  d C = 2  r 8 cm cm 2 C =  d C=  x 8 C = 25.1 cm (1 dp) C =  d C=  x 9.5 C = 29.8 cm (1 dp)

C = 2  r C = 2 x  x 3 C = 18.8 mm (1 dp) C = 2  r C = 2 x  x 2.1 C = 13.2 m (1 dp) The Circumference of a Circle Find the circumference of the following circles. C =  d C = 2  r 3 mm m 3

The Circumference of a Circle Find the perimeter of the following semi-circles. C =  d C = 2  r 8 cm cm 2 Perimeter = ½  d + d = ½ x  x = 20.6 cm (1 dp) Perimeter = ½  d + d = ½ x  x = 24.4 cm (1 dp)

Perimeter = ¼ ( 2  r) + 2r = ¼ x 2 x  x x 6 = 21.4 cm (1 dp) Perimeter = ¾(2  r) + 2r = ¾ x 2 x  x x 8.5 = 57.1 cm (1 dp) The Circumference of a Circle Find the perimeter of the ¼ and ¾ circles. C =  d C = 2  r cm 8.5 cm

The Circumference of a Circle Find the diameter/radius of the following circles. C =  d C = 2  r C = 25 cm find the diameter. 5 6  d = 25 d = 25/  d = 8.0 cm (1 dp) 2  r = 30 r = 30/(2  ) r = 4.8 cm (1 dp) C = 30 cm find the radius.