In a bar chart, 8 tons are represented by a straight bar of 2 cm, and 12 tons are represented by a straight bar of how many centimeters long.
在一幅条形统计图里，用2厘米的直条表示8吨，用多少厘米长的直条表示12吨．
<gadget id="calculator">8 / 2</gadget>
<output>4</output>

<gadget id="calculator">12 / 4</gadget>
<output>3</output>

<result>3</result>