A is 8 years old this year, and B is 2 years old this year. After many years, B's age will be half of A's.
甲今年8岁，乙今年2岁，再过多少年，乙的年龄是甲的一半．
<gadget id="calculator">2 / 1</gadget>
<output>2</output>

<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">8 * (1/2)</gadget>
<output>4</output>

<gadget id="calculator">4 - 2</gadget>
<output>2</output>

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

<gadget id="calculator">2 / (1/2)</gadget>
<output>4</output>

<result>4</result>