Maverick asked his grandpa's age, and grandpa said: "Your father and I are 106 years old this year. I was 38 years older than your father 10 years ago." Please help Maverick calculate his grandpa's age.
小牛问爷爷的年龄，爷爷说："我与你爸爸今年共106岁，10年前我比你爸爸大38岁"，请你帮小牛算算小牛爷爷的年龄．
<gadget id="calculator">106 + 38</gadget>
<output>144</output>

<gadget id="calculator">144 / 2</gadget>
<output>72</output>

<result>72</result>