A bag of rice is used up in three days. Use (1/5) on the first day, use the rest (2/5) on the second day, and use 31 kilograms more than the sum of the previous two days (5/8) on the third day, then this bag of rice has a total of How many kilograms.
一袋大米，三天用完．第一天用去(1/5)，第二天用去余下(2/5)，第三天用去的比前两天总和的(5/8)还多31千克，则这袋大米共有多少千克．
<gadget id="calculator">31 / 200</gadget>
<output>31/200 = around 0.155</output>

<gadget id="calculator">31 / (31/200)</gadget>
<output>200</output>

<result>200</result>