It takes a worker 15.2 hours to make a certain part, which is 24% shorter than the original plan. How many hours less than the original plan?
一个工人制造某种零件，实际用了15.2小时，比原计划用时缩短了24%，比原计划少用多少小时？
<gadget id="calculator">24 / 100</gadget>
<output>6/25 = around 0.24</output>

<gadget id="calculator">1 - (6/25)</gadget>
<output>19/25 = around 0.76</output>

<gadget id="calculator">15.2 / (19/25)</gadget>
<output>20</output>

<gadget id="calculator">20 - 15.2</gadget>
<output>4.8</output>

<result>4.8</result>