Question

The dimensions of a cuboid are in the ratio 2:3:4 and its total surface area is 8788cm2. Find the dimensions of thecuboid.

Answer 1

let the common factor be x..so the dimensions of the cuboid are 2x,3x and 4x...so the total surface area of the cuboid = 8788 cm^2 = 2(4x*3x +3x*2x+2x*4x) => 8788 = 2(12x^2+6x^2+8x^2) => 8788 = 2(26x^2) => 8788/2*26 =x^2 => 169 = x^2 => 13 =x..so ..the dimensions are..13*2=26cm,13*3=39 cm and 13*4=52 cm...

Answer 2

let it be 2x,3x,4x
a=8788cm2
a=2[lb+bh+hl]
8788=2[2x*3x+3x*4x+4x*2x]
8788/2=[6xx+12xx+8xx]
4394=26xx
xx=4394/26
xx=169
x=13
2x=2*13=26cm
3x=3*13=39cm
4x=4*13=52cm