Uncle Wang processes X parts per hour. He works 4 hours in the morning and 3.5 hours in the afternoon. How many X parts can he process in a day?
王叔叔每小时加工X个零件，他上午工作4小时，下午工作3.5小时，他一天可以加工零件多少X个．
<gadget id="calculator">4 + 3.5</gadget>
<output>7.5</output>

<result>7.5</result>