This year, my daughter is 36 years younger than her father. Five years ago, her daughter's age was 20% of her father's. How old is dad this year?
今年女儿比爸爸小36岁，五年前女儿的年龄是爸爸的20%．今年爸爸多少岁？
<gadget id="calculator">20 / 100</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">5 * (1/5)</gadget>
<output>1</output>

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

<gadget id="calculator">36 + 4</gadget>
<output>40</output>

<gadget id="calculator">1 - (1/5)</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">40 / (4/5)</gadget>
<output>50</output>

<result>50</result>