After the 70 cm long cylinder is cut into two small cylinders according to the ratio of 7:3, the surface area increases by 6 square centimeters compared to the original one. What is the difference in the volume of the two cylinders?
把70厘米长的圆柱按7：3截成两个小圆柱后，表面积比原来增加了6平方厘米，这两个圆柱的体积相差多少？
<gadget id="calculator">6 / 2</gadget>
<output>3</output>

<gadget id="calculator">7 + 3</gadget>
<output>10</output>

<gadget id="calculator">7 / 10</gadget>
<output>7/10 = around 0.7</output>

<gadget id="calculator">70 * (7/10)</gadget>
<output>49</output>

<gadget id="calculator">3 * 49</gadget>
<output>147</output>

<gadget id="calculator">3 / 10</gadget>
<output>3/10 = around 0.3</output>

<gadget id="calculator">70 * (3/10)</gadget>
<output>21</output>

<gadget id="calculator">3 * 21</gadget>
<output>63</output>

<gadget id="calculator">147 - 63</gadget>
<output>84</output>

<result>84</result>