The school planned to invest 4.2 million yuan in building a teaching building, but the actual investment was saved (1/7) compared with the original plan. How much was the actual savings compared to the original plan?
学校建教学楼，原计划投资420万元，实际投资比原计划节约了(1/7)，问实际比原计划节约了多少万元？
<gadget id="calculator">1 / 7</gadget>
<output>1/7 = around 0.142857</output>

<gadget id="calculator">420 * (1/7)</gadget>
<output>60</output>

<result>60</result>