A bunch of apples are sold (2/7), and the remaining ones are 90kg more than the sold ones. How many kilograms are in this pile of apples?
一堆苹果卖出(2/7)，这时剩下的比卖出的多90kg．这堆苹果原有多少千克？
<gadget id="calculator">2 / 7</gadget>
<output>2/7 = around 0.285714</output>

<gadget id="calculator">1 - (2/7) - (2/7)</gadget>
<output>3/7 = around 0.428571</output>

<gadget id="calculator">90 / (3/7)</gadget>
<output>210</output>

<result>210</result>