Chaoyang Primary School expanded the teaching building with an actual investment of 1.2 million yuan, which was more (1/5) than the original planned investment. How much is the original plan to invest?
朝阳小学扩建教学楼，实际投资120万元，比原计划投资多用(1/5)．原计划投资多少万元？
<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">1 + (1/5)</gadget>
<output>6/5 = around 1.2</output>

<gadget id="calculator">120 / (6/5)</gadget>
<output>100</output>

<result>100</result>