the total surface area of a solid right circular cylinder is 231 cm sq if curved surface area is two third of the total surface area ,determine the radius of its base and height
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TSA = 231 cm²
CSA = ⅔ * TSA = ⅔ * 231 = 154 cm²
TSA = 2πr(r+h), CSA = 2πrh
therefore
TSA - CSA = 77 cm² = 2πr²+2πrh - 2πrh
2 * 22/7 * r² = 77
44r² = 539
4r² = 49
r = 7/2 cm = 3.5 cm
inserting value of r:
154 = 2 * 22/7 * 3.5 * h
154 = 22h
h = 7 cm
therefore the base radius of the cylinder is 3.5 cm and its height is 7 cm
CSA = ⅔ * TSA = ⅔ * 231 = 154 cm²
TSA = 2πr(r+h), CSA = 2πrh
therefore
TSA - CSA = 77 cm² = 2πr²+2πrh - 2πrh
2 * 22/7 * r² = 77
44r² = 539
4r² = 49
r = 7/2 cm = 3.5 cm
inserting value of r:
154 = 2 * 22/7 * 3.5 * h
154 = 22h
h = 7 cm
therefore the base radius of the cylinder is 3.5 cm and its height is 7 cm
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