A cylindrical iron block with a volume of 90 cubic centimeters is processed into a conical iron block with a height of 6 cm. What is the bottom surface of the conical iron block?
把一个体积是90立方厘米的圆柱形铁块，加工成一个高是6厘米的圆锥形铁块，圆锥形铁块的底面是多少？
<gadget id="calculator">3 / 6</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">90 * (1/2)</gadget>
<output>45</output>

<result>45</result>