Question

the dimensions of a cuboid are 64cm×27cm×8cm. By how many sq. cm its total surface area greater than the total surface area of of a cube of equal volume​

Answer 1

first find total surface are of cuboid= 2(lb + bh + hl)

so l = 64 cm , b = 27 cm ,h = 8cm

so total surface are of cuboid = 2(64 x 27 + 27 x 8 + 8 x 64)

                                              = 2(2456)  

                                              = 4912 cm^2

and volume of cube = a1 x a2 x a3  = 13824 cm^3  

then

(side)a = cube root of 13824 = 24 cm

then total surface are of cube = 6(side)^2  = 6(44)^2 = 3456 cm^2

then 4912 - 3456 = 1456 cm^2,  total surface area of cuboid is greater than the total surface area of a cube.