The street garden covers a total area of (9/10) hectares, of which the lawn covers (1/5) hectare, and the flower garden occupies (1/4) of the total area. How much smaller is the area of the lawn than the flower garden?
街心花园共占地(9/10)公顷，其中草坪占地(1/5)公顷，花圃占地相当于总面积的(1/4)，草坪的面积比花圃的面积小多少？
<gadget id="calculator">9 / 10</gadget>
<output>9/10 = around 0.9</output>

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

<gadget id="calculator">(9/10) * (1/4)</gadget>
<output>9/40 = around 0.225</output>

<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">(9/40) - (1/5)</gadget>
<output>1/40 = around 0.025</output>

<result>1/40 = around 0.025</result>