In a vegetable field, (4/7) grow tomatoes, (3/7) grow cucumbers, and the rest grow potatoes. What percentage of the vegetable land is planted with potatoes?
一块菜地的(4/7)种西红柿，(3/7)种黄瓜，剩余的种土豆．种土豆的面积占这块菜地的几分之几？
<gadget id="calculator">4 / 7</gadget>
<output>4/7 = around 0.571429</output>

<gadget id="calculator">3 / 7</gadget>
<output>3/7 = around 0.428571</output>

<gadget id="calculator">1 - (4/7) - (3/7)</gadget>
<output>0</output>

<result>0</result>