Grandpa Wang uses (1/4) of the total land area of his family to grow eggplants, (3/5) to grow cucumbers, and the rest to grow tomatoes. What percentage of the total area is planted with tomatoes?
王爷爷用自家土地总面积的(1/4)种茄子、(3/5)种黄瓜，其余的种西红柿．种西红柿的面积占总面积的几分之几？
<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">3 / 5</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">1 - (1/4) - (3/5)</gadget>
<output>3/20 = around 0.15</output>

<result>3/20 = around 0.15</result>