The father is 50 years old and the daughter is 14 years old. Ask how many years ago, the age of the father was 5 times the age of the daughter.
父亲现年50岁，女儿现年14岁，问多少年前，父亲的年龄是女儿年龄的5倍．
<gadget id="calculator">50 - 14</gadget>
<output>36</output>

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

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

<gadget id="calculator">14 - 9</gadget>
<output>5</output>

<result>5</result>