Dad was on a business trip in Shanghai from April 27th to May 3rd. How many days did Dad travel in total?
爸爸从4月27日到5月3日在上海出差，爸爸一共出差多少天．
<gadget id="calculator">30 - 27</gadget>
<output>3</output>

<gadget id="calculator">3 + 1 + 3</gadget>
<output>7</output>

<result>7</result>