After cutting off a cube with a side length of 4 cm from a cuboid, what remains is a cuboid with a volume of 80 cubic centimeters. What is the longest side of the original cuboid in centimeters?
从一个长方体上截下一个棱长4厘米的正方体后，剩下的是一个长方体，它的体积是80立方厘米，原来长方体最长的一条棱是多少厘米．
<gadget id="calculator">4 * 4</gadget>
<output>16</output>

<gadget id="calculator">80 / 16</gadget>
<output>5</output>

<gadget id="calculator">5 + 4</gadget>
<output>9</output>

<result>9</result>