The perimeter of a rectangle is 2dm, the width is (1/4)dm, what is the length?
一个长方形周长是2dm，宽是(1/4)dm，长是多少？
<gadget id="calculator">2 / 2</gadget>
<output>1</output>

<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">1 - (1/4)</gadget>
<output>3/4 = around 0.75</output>

<result>3/4 = around 0.75</result>