Two people, A and B, process a batch of parts. A processes for 1.5 hours first, and then B joins in. When the task is completed, A completes (5/8) of this batch of parts. It is known that the work-efficiency ratio of A and B is 3:2, how many hours does it take for A to process this batch of parts alone?
甲乙两人加工一批零件，甲先加工1.5小时，乙再加入，完成任务时，甲完成这批零件的(5/8)．已知甲乙两人的工效比是3：2，则甲单独加工完成这批零件需多少小时？
<gadget id="calculator">5 / 8</gadget>
<output>5/8 = around 0.625</output>

<gadget id="calculator">1 - (5/8)</gadget>
<output>3/8 = around 0.375</output>

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

<gadget id="calculator">(3/8) * (3/2)</gadget>
<output>9/16 = around 0.5625</output>

<gadget id="calculator">(5/8) - (9/16)</gadget>
<output>1/16 = around 0.0625</output>

<gadget id="calculator">1.5 / (1/16)</gadget>
<output>24</output>

<result>24</result>