If the length of a rectangle is increased by (1/4) and its width is increased by (1/5), by what fraction is the area increased?
一个长方形的长增加了(1/4)，宽增加了(1/5)，则面积增加了几分之几？
<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<result>1/2 = around 0.5</result>