There is a basket of apples, 40% of which are sold for the first time, and the weight of the second sale is 10 kg more than the first time. At this time, there are still 40 kg of apples in the basket. How much does this basket of apples weigh?
有一筐苹果，第一次卖出40%，第二次卖出的重量比第一次多10千克，这时筐里还有苹果40千克，这筐苹果重多少千克？
<gadget id="calculator">40 + 10</gadget>
<output>50</output>

<gadget id="calculator">40 / 100</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">1 - (2/5) - (2/5)</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">50 / (1/5)</gadget>
<output>250</output>

<result>250</result>