The father is 40 years old this year, and the age of the daughter is (3/10) the age of the father, so how old is the daughter younger than the father?
今年爸爸40岁，女儿的岁数是爸爸岁数的(3/10)，那么女儿比爸爸小几岁？
<gadget id="calculator">3 / 10</gadget>
<output>3/10 = around 0.3</output>

<gadget id="calculator">40 * (3/10)</gadget>
<output>12</output>

<gadget id="calculator">40 - 12</gadget>
<output>28</output>

<result>28</result>