Ask the child's age, and answer: "10 years less than half of the father." Ask the father's age, and answer: "3 times more than the child's age." How old is the child's age?
向孩子问年龄，回答："比父亲的一半少10岁"向父亲问年龄，回答说："比孩子的岁数的3倍多3．"孩子的年龄是多少岁．
<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">(1/2) * 3</gadget>
<output>3/2 = around 1.5</output>

<gadget id="calculator">10 - (3/2)</gadget>
<output>17/2 = around 8.5</output>

<gadget id="calculator">(3/2) - 1</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">(17/2) / (1/2)</gadget>
<output>17</output>

<result>17</result>