When Wang Hua was 3 years old, his father was 33 years old. When Wang Hua's age was his father's (4/7), his father died of illness. How old was Wang Hua's father when he died?
王华3岁时，其父亲33岁，当王华的年龄是父亲的(4/7)那一年，父亲因病去世，王华父亲去逝世时多少岁？
<gadget id="calculator">33 - 3</gadget>
<output>30</output>

<gadget id="calculator">4 / 7</gadget>
<output>4/7 = around 0.571429</output>

<gadget id="calculator">1 - (4/7)</gadget>
<output>3/7 = around 0.428571</output>

<gadget id="calculator">30 / (3/7)</gadget>
<output>70</output>

<result>70</result>