In a vegetable field, (2/7) grow tomatoes, (4/7) grow cucumbers, and the rest grow eggplants. How much of the whole land is planted with eggplants?
一块菜地的(2/7)种西红柿，(4/7)种黄瓜，剩下的种茄子．种茄子的地占整块地的多少．
<gadget id="calculator">2 / 7</gadget>
<output>2/7 = around 0.285714</output>

<gadget id="calculator">4 / 7</gadget>
<output>4/7 = around 0.571429</output>

<gadget id="calculator">1 - (2/7) - (4/7)</gadget>
<output>1/7 = around 0.142857</output>

<result>1/7 = around 0.142857</result>