For a project, the actual investment is 5.1 million yuan, which is 15% less than the plan. How much is the planned investment?
一项工程，实际投资510万元，比计划节约15%，计划投资多少万元？
<gadget id="calculator">15 / 100</gadget>
<output>3/20 = around 0.15</output>

<gadget id="calculator">1 - (3/20)</gadget>
<output>17/20 = around 0.85</output>

<gadget id="calculator">510 / (17/20)</gadget>
<output>600</output>

<result>600</result>