The respective ratio of curved surface area and total surface area of a cylinder is 4:5. If the curved surface area of the cylinder is 1232 cm2. What is the height ?(in cm)
Let the height and the radius of cylinder be h cm and rcm respectively.
According to question,
2Πrh/2Πrh[r+h] = 4/5
⇒ 5h = 4r+4h
⇒ h = 4r
Curved surface area of cylinder = 1232
2Πrh = 1232
2×22/7×h/4×h = 1232
h2 = 28×28
h = 28 cm
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