alleryThree cubes of edge b are joined in a row. What is the surface area of the cuboid formed?
A18b2
B16b2
C14b2
D12b2
Answer & Solution
Correct answer: C. 14b2
1. Three separate cubes would have 3 × 6b2 = 18b2.
2. Two joins hide 4 faces in total, 4b2.
3. Surface area = 18b2 − 4b2 = 14b2.
_Source: NCERT Class 8 Mathematics, Chapter 9 Mensuration, 9.4.2 Cube_
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