It is known that the upper base of an isosceles trapezoid is 10 cm, the lower base is 25 cm, and the waist is 15 cm. What is its circumference in cm?
已知等腰梯形的上底是10厘米，下底是25厘米，腰是15厘米，那么它的周长是多少厘米．
<gadget id="calculator">15 * 2</gadget>
<output>30</output>

<gadget id="calculator">30 + 10 + 25</gadget>
<output>65</output>

<result>65</result>