Here is a cuboid, 80 cm
30 cm
30 cm
Work out the total surface area of this cuboid.
(4)

Explanation is in the file

cutt.ly/nz6VGda

Length = 80

Breadth = 30  

Height = 30

Total surface area of a cuboid is=

2 ( lb + bh + hl )

Putting the values in the formula,

We get,

= 2 [ (80 x 30) + (30 x 30) + (30 x 80)]

= 2 (2400 + 900 + 2400)

= 8100 cm²

THANK YOU!!

∝ Sidhdi

your welcome haha, this is the best place to find answers

area of part 1:

a1=base*height/2=(8+2)*(8-2-2-1)/2=10*3/2=15 ft^2

area of part 2:

a2=length*width=(8+2)*1=10 ft2

area of part 3:

a3=length*width=8*2=16 ft2

total shaded area : a1+a2+a3=41 ft2

total area of the reactangle : a=16*8=128 ft2

total area of the nonshaded region : 128-41=87 ft2