Last year, Dad's age was four times that of Xiaoming's. This year, Xiaoming is 10 years old. How old is dad?
去年爸爸的年龄是小明的4倍，今年小明10岁．爸爸今年多少岁？
<gadget id="calculator">10 - 1</gadget>
<output>9</output>

<gadget id="calculator">9 * 4</gadget>
<output>36</output>

<gadget id="calculator">36 + 1</gadget>
<output>37</output>

<result>37</result>