Divide the bottom surface of a cylinder into many equal sectors, and then cut the cylinder according to the radius of the sectors to form an approximate cuboid. The surface area of the cuboid is 24 square decimeters larger than the surface area of the cylinder. Find the original cylinder What is the lateral area?
把一个圆柱底面分成许多相等的扇形，然后把圆柱体按扇形的半径一一切开，拼成一个近似的长方体，长方体的表面积比圆柱体的表面积增加了24平方分米，求原来圆柱体的侧面积是多少？
<gadget id="calculator">3.14 * 2 * 12</gadget>
<output>75.36</output>

<result>75.36</result>