Master Wang processes 45 parts in 5 hours, and Master Ding processes 7 parts per hour. How many more parts does Master Wang process than Master Ding per hour?
王师傅5小时加工45个零件，丁师傅每小时加工7个零件，王师傅每小时比丁师傅多加工几个零件？
<gadget id="calculator">45 / 5</gadget>
<output>9</output>

<gadget id="calculator">9 - 7</gadget>
<output>2</output>

<result>2</result>