Roll a piece of paper 5 decimeters long and 3 decimeters wide into a cylinder. What is the lateral area of the cylinder in square centimetres.
把一个长5分米，宽3分米的纸卷成一个圆柱体．圆柱体的侧面积是多少平方分米．
<gadget id="calculator">5 * 3</gadget>
<output>15</output>

<result>15</result>