Find the TSA of a cuboid 8 cm × 6 cm × 5 cm.

Class 8MensurationMensuration

Step-by-Step Solution

TSA = 2(lb + bh + hl) =

2 (8 \times 6 + 6 \times 5 + 5 \times 8) = 2 (48 + 30 + 40) = 2 \times 118 = 236 cm^{2}

Answer: A) 236

A cuboid has 3 pairs of identical opposite faces. Their total area:

- 2 faces of

l \times b

(top + bottom)
- 2 faces of

b \times h

(front + back)
- 2 faces of

l \times h

(left + right)

**TSA of cuboid =

2 (l b + bh + h l)

.**
**LSA of cuboid =

2 h (l + b)

** — only the four side walls, used for room painting (not floor/ceiling).

Special case (cube,

l = b = h = s

): TSA =

6 s^{2}

, LSA =

4 s^{2}

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