On the way to school, Xiao Ming heard two people talking about their respective ages, and only one person said "When my age is your current age, you are only 4 years old." The other person said "When my age is your current age You will be 61 years old at the time, "How old is the younger of the two of them now.
上学的路上，小明听到两个人在谈论各自的年龄，只听一人说"当我的年龄是你现在的年龄时，你才4岁．"另一人说"当我的年龄是你现在的年龄时，你将61岁，"他们两人中，年龄较小的现在多少岁．
<gadget id="calculator">61 - 4</gadget>
<output>57</output>

<gadget id="calculator">57 / 3</gadget>
<output>19</output>

<gadget id="calculator">19 + 4</gadget>
<output>23</output>

<result>23</result>