A batch of cement was transported by car, the first transported 168 tons, accounting for (4/5) of the total cement, the second transported was the first (1/4), and it happened to be finished. How many tons is this batch of cement?
用汽车运一批水泥，第一次运了168吨，占水泥总数的(4/5)，第二次运的是第一次的(1/4)，正好运完．这批水泥有多少吨？
<gadget id="calculator">4 / 5</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">168 / (4/5)</gadget>
<output>210</output>

<result>210</result>