A triangle vegetable field, its three sides are 15 meters, 12 meters and 7 meters long respectively, what is the perimeter of this triangle vegetable field?
一块三角形菜地，它的三条边分别长15米、12米和7米，这个三角形菜地的周长是多少．
<gadget id="calculator">15 + 12 + 7</gadget>
<output>34</output>

<result>34</result>