If you buy a car, you will get 10% discount for one-time cash payment. If you pay in installments, the original price will be increased by 10%. Xiaoming's father did the math and found that buying in cash was 8,400 yuan cheaper than paying in installments. Do you know how much the original price of this car was?
购买一辆汽车，一次性现金付款打九折，如果分期付款购买要比原来加价10%．小明爸爸算了算，发现现金购买比分期付款便宜了8400元，你知道这辆汽车原价是多少元吗？
<gadget id="calculator">8_400 / 0.2</gadget>
<output>42_000</output>

<result>42_000</result>