A project, the actual investment is 40 million yuan, saving (1/5) compared with the original plan, and how many yuan is saved compared with the original plan.
一项工程，实际投资4000万元，比原计划节约(1/5)，比原计划节约了多少万元．
<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">1 - (1/5)</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">4_000 / (4/5)</gadget>
<output>5_000</output>

<gadget id="calculator">5_000 * (1/5)</gadget>
<output>1_000</output>

<result>1_000</result>