The (2/7) on the blackboard is "Mathematics World", and the rest are "Workplace Garden". How much more of this blackboard is used in the "Exercise Corner" than in the "Mathematics World"?
黑板报的(2/7)是"数学天地"，其余是"习作园地"．"习作园地"比"数学天地"多用了这块黑板的几分之几？
<gadget id="calculator">2 / 7</gadget>
<output>2/7 = around 0.285714</output>

<gadget id="calculator">1 - (2/7)</gadget>
<output>5/7 = around 0.714286</output>

<gadget id="calculator">(5/7) - (2/7)</gadget>
<output>3/7 = around 0.428571</output>

<result>3/7 = around 0.428571</result>