There are three iron cubes whose surface areas are 24cm**2, 54cm**2 and 294cm**2 respectively. Now melt and cast these three iron blocks into a big cube, find the volume of the big cube.
有三个正方体铁块，它们的表面积分别是24cm**2、54cm**2和294cm**2．现将这三个铁块熔铸成一个大正方体，求大正方体的体积．
<gadget id="calculator">2 ** 3</gadget>
<output>8</output>

<gadget id="calculator">3 ** 3</gadget>
<output>27</output>

<gadget id="calculator">7 ** 3</gadget>
<output>343</output>

<gadget id="calculator">8 + 27 + 343</gadget>
<output>378</output>

<result>378</result>