The younger brother is 4 years old this year, and the older brother is 12 years old this year. After 10 years, how old is the older brother than the younger brother?
弟弟今年4岁，哥哥今年12岁，10年后，哥哥比弟弟大几岁？
<gadget id="calculator">12 - 4</gadget>
<output>8</output>

<result>8</result>