A right-angled trapezoid has an upper base of 3 cm and a waist length of 10 cm. If the upper base is increased by 5 cm, it becomes a square. What is the perimeter of the trapezoid in cm?
一个直角梯形，上底3厘米，一腰长10厘米，如果把它的上底增加5厘米，就变成一个正方形，这个梯形的周长是多少厘米？
<gadget id="calculator">3 + 5</gadget>
<output>8</output>

<gadget id="calculator">8 * 2</gadget>
<output>16</output>

<gadget id="calculator">3 + 16 + 10</gadget>
<output>29</output>

<result>29</result>