Uncle Wang plans to plant trees on the contracted barren hills next year. Among them, (2/5) will be planted with pine trees, (1/2) will be planted with apple trees, and the rest will be planted with pear trees. What percentage of the area will be pear trees?
王大伯计划明年在承包的荒山上植树，其中的(2/5)栽种松树，(1/2)栽种苹果树，其余的面积栽种梨树，梨树面积占几分之几？
<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">1 - (2/5) - (1/2)</gadget>
<output>1/10 = around 0.1</output>

<result>1/10 = around 0.1</result>