There are 180 kilograms of apples, sell (2/9), how many kilograms are left.
有180千克的苹果，卖出它的(2/9)，还剩多少千克．
<gadget id="calculator">2 / 9</gadget>
<output>2/9 = around 0.222222</output>

<gadget id="calculator">1 - (2/9)</gadget>
<output>7/9 = around 0.777778</output>

<gadget id="calculator">180 * (7/9)</gadget>
<output>140</output>

<result>140</result>