There are three ropes, the first one is 23 meters long, the second one is 7 meters longer than the first one, and 7 meters shorter than the third one, and the third rope is (how many) meters long.
有三根绳子，第一根长23米，第二根比第一根长7米，比第三根短7米，第三根绳子长(多少)米．
<gadget id="calculator">23 + 7 + 7</gadget>
<output>37</output>

<result>37</result>