The length of a rectangle is extended (1/4), and the width is extended (1/5), how much is the area of the rectangle now increased compared to the original
一个长方形的长延长(1/4)，宽延长(1/5)，现在长方形的面积比原来增加了多少
<gadget id="calculator">3 / 2</gadget>
<output>3/2 = around 1.5</output>

<gadget id="calculator">(3/2) - 1</gadget>
<output>1/2 = around 0.5</output>

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