The environmental protection department invested 1.5 million yuan in the first phase of treating a sewage river, and the second phase accounted for 30% of the total investment. Another 2 million yuan was invested to complete the treatment. How much yuan did the environmental protection department invest in total?
环环保部门治理一条污水河，一期投入150万，二期投入占总投入的30%，再投入200万元就可以治理完，环保部门共投入多少万元？
<gadget id="calculator">150 + 200</gadget>
<output>350</output>

<gadget id="calculator">30 / 100</gadget>
<output>3/10 = around 0.3</output>

<gadget id="calculator">1 - (3/10)</gadget>
<output>7/10 = around 0.7</output>

<gadget id="calculator">350 / (7/10)</gadget>
<output>500</output>

<result>500</result>