Xiao Wang and Xiao Li respectively produce the same kind of parts in the same quantity. Xiao Wang first produces at the rate of 12 per hour, and later at the rate of 9 per hour. It takes 55 minutes to complete the work. Xiao Li first produced at the rate of 8 per hour, and then at the rate of 4 per hour. It took 1.5 hours to complete. It is known that the total amount of work in the first section of Xiaowang is equal to the total amount of work in the previous section of Xiaoli. How many parts are produced by the two?
小王和小李各自生产数量相同的同种零件，小王先以每小时12个的效率生产，后来又用每小时9个的效率生产，完工时共用55分钟．小李则先用每小时8个的效率生产，后又用每小时4个的效率生产，一共用1.5小时才完成．已知小王后一段的工作总量与小李前一段的工作总量相等，求两人共生产多少个零件？
<gadget id="calculator">12 * 0.25</gadget>
<output>3</output>

<gadget id="calculator">11 / 12</gadget>
<output>11/12 = around 0.916667</output>

<gadget id="calculator">(11/12) - 0.25</gadget>
<output>0.666667</output>

<gadget id="calculator">9 * 0.666667</gadget>
<output>6.000003</output>

<gadget id="calculator">3 + 6.000003</gadget>
<output>9.000003</output>

<gadget id="calculator">2 * 9.000003</gadget>
<output>18.000006</output>

<result>18.000006</result>