A 1 meter long wire is used to form an isosceles trapezoid with a waist length of 15 cm and a height of 10 cm. What is the area of the trapezoid in square centimeters?
用一根1米长的铁丝围成一个等腰梯形，腰长15厘米，高10厘米，这个梯形的面积是多少平方厘米．
<gadget id="calculator">1 * 100</gadget>
<output>100</output>

<gadget id="calculator">15 * 2</gadget>
<output>30</output>

<gadget id="calculator">100 - 30</gadget>
<output>70</output>

<gadget id="calculator">10 / 2</gadget>
<output>5</output>

<gadget id="calculator">70 * 5</gadget>
<output>350</output>

<result>350</result>