After the surface area of a cube is painted the cube is cut into 64 smaller cubes of same dimensions. How many have no face painted? 1 face painted? 2 faces painted? 3 faces painted?
Note that lateral surface area of a cylinder is the circumference of base x height of cylinder. Can we write lateral surface area of a cuboid as perimeter of base x height of cuboid?
Total surface area of a suitcase = 2(lb + bh + hl)
= 2(80 x 48 + 48 x 24 + 24 x 80)
= 2(3840 + 1152 + 1920) cm2
= 2(6912) cm2
= 13824 cm2
∴ Total S.A. of 100 suitcases = 100 x 13824 cm2 = 1382400 cm2
Surface area of 1 m of tarpaulin = 100 cm x 96 cm
= 9600 cm2
i.e. 1 m of tarpaulin can cover 9600 cm2 surface
∴ metres of tarpaulin will cover the total surfaces of 100 suitcases
i.e. or 144 metres of tarpaulin will be required to cover 100 suitcases.