Master Wang processed 210 parts in the morning and 280 parts in the afternoon. If he processes 70 pieces per hour, how many more hours does he process in the afternoon than in the morning?
王师傅上午加工210个零件，下午加工了280个零件．如果每小时加工70个，他下午比上午多加工几小时？
<gadget id="calculator">280 / 70</gadget>
<output>4</output>

<gadget id="calculator">210 / 70</gadget>
<output>3</output>

<gadget id="calculator">4 - 3</gadget>
<output>1</output>

<result>1</result>