Master Zhang produces 576 parts in 6 hours, and Master Li produces 460 parts in 4 hours. On average, how many parts does Master Zhang produce less than Master Li per hour?
张师傅6小时生产576个零件，李师傅4小时生产460个零件．张师傅平均每小时比李师傅少生产多少个零件？
<gadget id="calculator">460 / 4</gadget>
<output>115</output>

<gadget id="calculator">576 / 6</gadget>
<output>96</output>

<gadget id="calculator">115 - 96</gadget>
<output>19</output>

<result>19</result>