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Question
In the example given below, the radius of the base of a cylinder and its height is given. Then find the curved surface area and total surface area.
r = 4.2 cm, h = 14 cm
Solution
We know that,
Curved surface area = 2πrh
Total surface area = 2πr(h + r)
Here, r = 4.2 cm, h = 14 cm
Curved surface area of a cylinder = 2πrh
= `2 xx 22/7 xx 4.2 xx 14`
= `44 xx 8.4`
= 369.6 sq.cm.
Total surface area of a cylinder = 2πr(h + r)
= `2 xx 22/7 xx 4.2(14 + 4.2)`
= `44 xx 0.6 xx 18.2`
= `26.4 xx 18.2`
= 480.48 sq.cm.
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