There is a batch of coal in the cafeteria. After some of it is used up, there are still (2/9) and (3/5) tons left. How many tons of coal are there in the cafeteria?
食堂里有一批煤，用去一部分后还剩(2/9)，还剩(3/5)吨，食堂原来有煤多少吨？
<gadget id="calculator">3 / 5</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">2 / 9</gadget>
<output>2/9 = around 0.222222</output>

<gadget id="calculator">(3/5) / (2/9)</gadget>
<output>27/10 = around 2.7</output>

<result>27/10 = around 2.7</result>