How many times will the area of the lateral surface of the cylinder increase if its height

How many times will the area of the lateral surface of the cylinder increase if its height is reduced by 3 times, and the radius is increased by 6 times.

Let the radius of the first cylinder be OA = R1 cm, and the height AB = h1 cm.

Then the area of the lateral surface of the original cylinder is equal to:

S1 side = 2 * π * R1 * h1.

The radius of the base of the second cylinder is equal to: ОА = 6 * R1 cm, and its height AB = h1 / 3 cm.

The lateral surface area of the second cylinder is:

S2 side = 2 * π * 6 * R1 * h1 / 3 = 4 * π * R1 * h1.

Then S2 side / S1 side = 4 * π * R1 * h1 / 2 * π * R1 * h1 = 2.

Answer: The lateral surface area will double.



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