There is a basket of apples. After selling (3/4), 4 kilograms are sold. At this time, there are 16 kilograms left. How many kilograms are there in this basket of apples?
有一筐苹果，卖出(3/4)后，又卖出4千克，这时还剩16千克，这筐苹果原有多少千克？
<gadget id="calculator">4 + 16</gadget>
<output>20</output>

<gadget id="calculator">3 / 4</gadget>
<output>3/4 = around 0.75</output>

<gadget id="calculator">1 - (3/4)</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">20 / (1/4)</gadget>
<output>80</output>

<result>80</result>