Congcong went to the supermarket to buy something. When paying, Congcong mistook a piece of 10 yuan for 1 yuan, and a piece of 5 yuan for 20 yuan, and paid the cashier. In the end, he paid a total of 100 yuan. So how much should Cong Cong actually pay?
聪聪去超市买到东西，付钱的时候聪聪将一张10元的，错看成一元的，将一张5元的错当成20元的付给了收银员，结果一共付款100元，那么聪聪实际应该付多少钱？
<gadget id="calculator">10 - 1</gadget>
<output>9</output>

<gadget id="calculator">20 - 5</gadget>
<output>15</output>

<gadget id="calculator">9 - 15</gadget>
<output>-6</output>

<gadget id="calculator">100 + (-6)</gadget>
<output>94</output>

<result>94</result>