The sum of the ages of Xiaohua and his father this year is 49 years old. In a year, the sum of the ages of Xiaohua and his father is a years old.
小华和爸爸今年的岁数和是49岁，再过a年，小华和爸爸的岁数和是多少a岁．
<gadget id="calculator">49 + 2</gadget>
<output>51</output>

<result>51</result>