Question

The dimensional of a cuboid are in the ratio 5ratio 3 ratio 1 and its total surface area is 414 m square. Find the dimension of the cuboid ​

Answer 1

let the dimensions of cuboid be 1x , 3x and 5x

total surface area = 2(lb+bh+hl)

414= 2(1x×3x+3x×5x+5x×1x)

414=2(3x^2 + 15x^2 + 5x^2)

414=2(23x^2)

414 = 46x^2

x^2 = 414/46

x^2=9

x=√9 =3

1x= 1×3 = 3

3x=3×3 = 9

5x = 5×3=15