Shera's Surface Area and Volume Post

Rectangular Prism

Top:

Length - 5m

Width - 10m

A = l x w

A = 5 x 10

A = 50m²

Front:

Length - 6m

Width - 10m

A = l x w

A = 6 x 10

A = 60m²

Side:

Length - 5m

Width - 6m

A = l x w

A = 5 x 6

A = 30m²

TSA = 2 (T+F+S)

= 2 (50+60+30)

= 2 (140)

= 280m²

Triangular Prism

Rectangle 1

Length - 8cm

Width - 5cm

A = l x w

A = 8 x 5

A = 40cm²

Rectangle 2

Length - 10cm

Width - 5cm

A = l x w

A = 10 x 5

A = 50cm²

Rectangle 3

Length - 9cm

Width - 5cm

A = l x w

A = 9 x 5

A = 45cm²

Triangle

A = b x h / 2

A = 8 x 9 / 2

A = 72 / 2

A = 36cm²

TSA = 40 + 50 + 45 + 36 + 36

= 207cm²

Cylinder

r = d / 2

r = 8mm / 2

r = 4mm

c = πd

c=3.14 x 8

c = 25.12

L x W

25.12 x 12 = 301.44

Area of a Circle:

AO = πr²

AO = 3.14 x 4 x 4

AO = 50.24

TSA = Rectangle + Circle + Circle

= 301.44 + 50.24 + 50.24

= 401.92mm²

VOLUME

v = (b x h / 2) x h

v = (3 x 5 / 2) x 8.5

v = (15 / 2) x 8.5

v = 7.5 x 8.5

v = 63.75m 3

v = l . w . h

v = 20 x 8 x 16

v = 2560cm 3

v = (b x h / 2) x 6.5

v = (4 x 8 / 2) x 6.5

v = (32 / 2) x 6.5

v = 16 x 6.5

v = 104cm 3

104 / 8 = 13

13 x 3 = 39cm 3

r = d / 2

r = 12 / 2

r = 6cm

v = πr2 x h

v = 3.14 x 6 x 6 x 15

v = 1695.6cm 3