The blades of a breeze ceiling fan are composed of three trapezoidal plastic sheets. It is known that the upper bottom of each plastic sheet is 3.2 cm, the lower bottom is 4.5 cm, and the height is 10 cm. The three blades of this ceiling fan need a total of plastic sheets How many square centimeters?
一种微风吊扇的叶片是由三块梯形的塑料片组成的，已知每块塑料片上底是3.2厘米，下底是4.5厘米，高是10厘米，做这个吊扇的三块叶片共需塑料片多少平方厘米？
<gadget id="calculator">3.2 + 4.5</gadget>
<output>7.7</output>

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

<gadget id="calculator">7.7 * 5</gadget>
<output>38.5</output>

<gadget id="calculator">38.5 * 3</gadget>
<output>115.5</output>

<result>115.5</result>