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The diameter and slant height of a conical tent are 16 m and 5.6 m respectively. What length of cloth of width 4 m is needed to make the tent?
A35.2 m
B32.5 m
C32 m
D35 m
Answer & Solution
Correct answer: A. 35.2 m
1. Radius r = 16/2 = 8 m; curved surface area = πrl = (22/7) × 8 × 5.6.
2. CSA = (22/7) × 44.8 = 140.8 m².
3. Length of cloth = area ÷ width = 140.8 / 4.
4. Length = 35.2 m.
_Source: RRB Group D CEN-02/2018 PYQ, Q.70._