The radius of a cylinder is doubled and its height is halved. Find the ratios of their surface areas.
1 answer:
Answer: 1:1
Step-by-step explanation:
Let r be the radius and h be the height of a cylinder.
Formula: Curved surface area of cylinder =
Now, if radius of a cylinder is doubled and its height is halved, then new radius will be R= 2r and new height will be
Now, new surface area =
Ratio of curved surface areas :
Hence, the ratios of their surface areas = 1:1 .
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<h2>Answer and Explanation to questions 19</h2>∠3 and ∠4 form a straight line. Therefore, ∠3 + ∠4 = 180° .......(i)
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