is a natural number, x/810=0.{_{a}**(•)}2{_{5}**(•)}, the letter a represents a number, what is x.
x是自然数，x/810=0.{_{a}**(•)}2{_{5}**(•)}，字母a表示一个数字，x是多少．
<gadget id="calculator">25 * 37</gadget>
<output>925</output>

<gadget id="calculator">30 / 37</gadget>
<output>30/37 = around 0.810811</output>

<gadget id="calculator">925 * (30/37)</gadget>
<output>750</output>

<result>750</result>