There are 400 kilograms of pears, sold in the morning (2/5), and sold the rest in the afternoon (5/6). How many are still unsold?
有400千克梨，上午卖出(2/5)，下午卖出剩下的(5/6)．还有多少没有卖出？
<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">1 - (2/5)</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">5 / 6</gadget>
<output>5/6 = around 0.833333</output>

<gadget id="calculator">(3/5) * (5/6)</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">1 - (2/5) - (1/2)</gadget>
<output>1/10 = around 0.1</output>

<gadget id="calculator">400 * (1/10)</gadget>
<output>40</output>

<result>40</result>