pile of yellow sand was transported away (2/3), exactly 60 tons were transported away, how many tons of yellow sand are left?
一堆黄沙，运走了(2/3)，正好运走60吨，还剩下黄沙多少吨？
<gadget id="calculator">2 / 3</gadget>
<output>2/3 = around 0.666667</output>

<gadget id="calculator">60 / (2/3)</gadget>
<output>90</output>

<gadget id="calculator">90 - 60</gadget>
<output>30</output>

<result>30</result>