A farm actually rehabilitated 10.5 hectares of saline-alkali land, which is 5% more than the original plan. How many hectares of saline-alkali land was originally planned?
某农场实际改造盐碱地10.5公顷，比原计划多改造5%，原计划改造盐碱地多少公顷？
<gadget id="calculator">5 / 100</gadget>
<output>1/20 = around 0.05</output>

<gadget id="calculator">1 + (1/20)</gadget>
<output>21/20 = around 1.05</output>

<gadget id="calculator">10.5 / (21/20)</gadget>
<output>10</output>

<result>10</result>