There is a rectangular threshing floor. If the length is increased by 3 meters and the width is increased by 8 meters, the threshing floor becomes a square, and the area increases by 251 square meters. So how many square meters is the area of the original threshing ground?
有一个长方形打谷场，如果长增加3米，宽增加8米，打谷场就变成了正方形，面积也就增加251平方米．那么原来打谷场的面积是多少平方米？
<gadget id="calculator">3 * 8</gadget>
<output>24</output>

<gadget id="calculator">251 + 24</gadget>
<output>275</output>

<gadget id="calculator">3 + 8</gadget>
<output>11</output>

<gadget id="calculator">275 / 11</gadget>
<output>25</output>

<gadget id="calculator">25 - 3</gadget>
<output>22</output>

<gadget id="calculator">25 - 8</gadget>
<output>17</output>

<gadget id="calculator">22 * 17</gadget>
<output>374</output>

<result>374</result>