10 cars form a convoy, each car is 3 meters long, and the distance between the front and rear cars is 4 meters, what is the total length of the convoy?
10辆汽车组成一个车队，每辆汽车车长3米，前后两辆车间距4米，这个车队全长多少米．
<gadget id="calculator">10 - 1</gadget>
<output>9</output>

<gadget id="calculator">4 * 9</gadget>
<output>36</output>

<gadget id="calculator">3 * 10</gadget>
<output>30</output>

<gadget id="calculator">36 + 30</gadget>
<output>66</output>

<result>66</result>