The actual construction cost of the new teaching building in Dongfang Primary School was 450,000 yuan, which was (1/10) less than the original plan. How much was the original plan?
东方小学新建教学大楼，实际造价45万元，比原计划节约了(1/10)．原计划造价多少万元？
<gadget id="calculator">1 / 10</gadget>
<output>1/10 = around 0.1</output>

<gadget id="calculator">1 - (1/10)</gadget>
<output>9/10 = around 0.9</output>

<gadget id="calculator">45 / (9/10)</gadget>
<output>50</output>

<result>50</result>