There is a basket of apples that weighs 42 kilograms. After half of the apples are sold, the weight of the basket is 22 kilograms. How many kilograms did the basket originally have?
有一筐苹果连筐重42千克，卖掉一半苹果后，连筐重22千克，这筐苹果原有多少千克？
<gadget id="calculator">42 - 22</gadget>
<output>20</output>

<gadget id="calculator">20 * 2</gadget>
<output>40</output>

<result>40</result>