Xiaoqing practiced rope skipping three times. The first time he jumped 68 times, the second time he jumped 78 times. If he wants to jump 80 times on average for three times, how many times should he jump the third time?
小青进行了3次跳绳练习，第一次跳了68下，第二次跳了78下，他要想三次平均跳80下，第三次要跳多少下？
<gadget id="calculator">80 * 3</gadget>
<output>240</output>

<gadget id="calculator">240 - 68 - 78</gadget>
<output>94</output>

<result>94</result>