The lateral area of a cylinder is 12.56 square meters, and the radius of the base is 4 decimeters. How many decimeters is its height?
一个圆柱的侧面积是12.56平方米，底面半径是4分米，它的高是多少分米？
<gadget id="calculator">3.14 * 4 * 2</gadget>
<output>25.12</output>

<gadget id="calculator">100 / 25.12</gadget>
<output>3.980892</output>

<gadget id="calculator">12.56 * 3.980892</gadget>
<output>50.000004</output>

<result>50.000004</result>