When Mr. Zhang came back from shopping and kept accounts, he found that the shopping money plus the remaining cash was 153.90 yuan more than the cash he brought. After careful calculation, I found that I misread the decimal point of a sum of money. So how much is the misunderstood shopping money actually worth?
张老师购物回来记账时发现，购物款加上剩余的现金比带去的现金多出153.90元．仔细核算后，发现有一笔购物款的小数点被自己看错了一位．则这笔被看错的购物款实际是多少元．
<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">153.9 / (9/10)</gadget>
<output>171</output>

<result>171</result>