Seven identical cubes, each of side 5 cm, are joined end-to-end to form a cuboid. Find the total surface area (in cm^2) of the resulting cuboid.

Introduction / Context:
Joining seven cubes of side 5 cm end-to-end yields a cuboid whose dimensions can be inferred. Then use the total surface area formula for a cuboid: TSA = 2(lw + lh + wh).

Given Data / Assumptions:

• Each cube side = 5 cm.
• Seven cubes in a line ⇒ length = 7 * 5 = 35 cm; width = 5 cm; height = 5 cm.

Concept / Approach:
Compute TSA with l = 35, w = 5, h = 5.

Step-by-Step Solution:

Verification / Alternative check:
Count exposed faces mentally: long faces (2), side faces (2), end faces (2) match TSA formula result.

Why Other Options Are Wrong:
They stem from forgetting one pair of faces or miscomputing one product.

Common Pitfalls:
Treating it as seven separate cubes and double-counting internal faces; arithmetic slips in multiplication.

Final Answer:
750 sq cm