A pile of coal, the pile of coal (2/5) was used in the first week, and the pile of coal (1/3) was used in the second week, there are still 60 tons left. How many tons is this pile of coal?
一堆煤，第一周用去这堆煤的(2/5)，第二周用去这堆煤的(1/3)，还剩下60吨．这堆煤共有多少吨？
<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">(2/5) + (1/3)</gadget>
<output>11/15 = around 0.733333</output>

<gadget id="calculator">1 - (11/15)</gadget>
<output>4/15 = around 0.266667</output>

<gadget id="calculator">60 / (4/15)</gadget>
<output>225</output>

<result>225</result>