In a statistical chart, there are 3 cm straight bars representing 60 tons, so how many centimeters should the length of the straight bars be to represent 120 tons?
在一幅统计图里有3厘米的直条表示60吨，那么要表示120吨的直条的长应为多少厘米．
<gadget id="calculator">60 / 3</gadget>
<output>20</output>

<gadget id="calculator">120 / 20</gadget>
<output>6</output>

<result>6</result>