The waist length of an isosceles trapezoid is 1.5 cm, the upper base is 1.5 times the waist length, and the lower base is twice the waist length. Find the perimeter of this isosceles trapezoid?
一个等腰梯形的腰长为1.5厘米，上底是腰长的1.5倍，下底是腰长的2倍，求这个等腰梯形的周长？
<gadget id="calculator">1.5 * 1.5</gadget>
<output>2.25</output>

<gadget id="calculator">1.5 * 2</gadget>
<output>3</output>

<gadget id="calculator">2.25 + 3 + 1.5 + 1.5</gadget>
<output>8.25</output>

<result>8.25</result>