Question

n.
10. Three equal cubes are placed adjacently in a row. Find the
ratio of total surface area of the new cuboid to that of the
sum of the surface areas of the three cubes.
​

Answer 1

Step-by-step explanation:

let the side of each equal cube be = x

sum of the surface area of 3 equal cubes = 6x² + 6x² + 6x² ( surface area of cube = 6a²)

= 18x²

Total surface area of resulting cuboid =2(lb+bh+lh)=2(3x² + x² + 3x²)=2(7x²)=14x²

Ratio of total surface area of cuboid to that of cube = 14x²/18x²

= 7/9

= 7:9