Two cubes each of edge 9 cm are joined to form a single cuboid. What is the total surface area of the cuboid formed?
Answer & explanation
Correct answer: option 2
The cuboid formed by joining two cubes is:
The dimensions of the newly formed cuboid is = 18 x 9 x 9
Total surface area of a cuboid (a x b x c) = 2(ab + bc + ac)
Total surface area of cuboid of dimensions 18 x 9 x 9 = 2[(18x9) + (9x9) + (18x9)]
= 2[162 + 81 162] = 2 x 405
= 810 cm²