This year, the sum of the ages of Xiaodong and his father is 46 years old. It is known that 3 years ago, his father's age was exactly four times that of Xiaodong. Do you know how old Xiaodong is this year? (solution by equation)
今年，小冬和爸爸年龄的和是46岁，已知3年前爸爸的年龄正好是小冬的4倍，你知道小冬今年多大吗？(用方程解)
<gadget id="calculator">3 * 2</gadget>
<output>6</output>

<gadget id="calculator">46 - 6</gadget>
<output>40</output>

<gadget id="calculator">1 + 4</gadget>
<output>5</output>

<gadget id="calculator">40 / 5</gadget>
<output>8</output>

<gadget id="calculator">8 + 3</gadget>
<output>11</output>

<result>11</result>