There are x chickens, and the number of ducks is (5/7) of chickens. How many ducks are there?
鸡有x只，鸭的只数是鸡的(5/7)，鸭有多少只．
<gadget id="calculator">5 / 7</gadget>
<output>5/7 = around 0.714286</output>

<result>5/7 = around 0.714286</result>