Mensurationhard · Past Paper
A cuboid has its length, breadth and height in the ratio 3:2:1 and its total surface area is 88 cm². Find its length.
A2 cm
B4 cm
C6 cm
D8 cm
✓ Correct Answer: C — 6 cm
2(3x*2x + 2x*x + x*3x) = 88 => 2(6x² + 2x² + 3x²) = 88 => 22x² = 88 => x² = 4 => x = 2. Length = 3 * 2 = 6 cm.
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