A chicken weighs 4 kg, and a duck weighs (1/2) kg. How much does the duck weigh?
一只鸡4千克，一只鸭比它重(1/2)千克，鸭重多少千克？
<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">4 + (1/2)</gadget>
<output>9/2 = around 4.5</output>

<result>9/2 = around 4.5</result>