Question
Download Solution PDFThe curved surface area of a cylinder is half of its total surface area. If the height is 128 cm, then find the radius (in cm).
Answer (Detailed Solution Below)
Detailed Solution
Download Solution PDFGiven:
Curved surface area (CSA) = 1/2 × Total surface area (TSA)
Height (h) = 128 cm
Formula used:
Curved surface area (CSA) = 2πrh
Total surface area (TSA) = 2πr(h + r)
Calculation:
CSA = 1/2 × TSA
⇒ 2πrh = 1/2 × 2πr(h + r)
⇒ h = 1/2 × (h + r)
⇒ 2h = h + r
⇒ r = 2h - h
⇒ r = h
⇒ r = 128 cm
∴ The correct answer is option (1).
Last updated on Jul 22, 2025
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