Question

Two identical solid cubes of side a are joined end to end. The total surface area of the resulting cuboid is ______.

Answer 1

Two identical solid cubes of side a are joined end to end. The total surface area of the resulting cuboid is 10a².

Explanation: 

The resulting cuboid has dimensions \[2a \times a \times a\], so its total surface area is \[2(2a^{2}+a^{2}+2a^{2})=10a^{2}\].