A computer is priced at 5,400 yuan this year, which is 10% lower than last year. How much did it sell for last year? (Solution of column equation)
一种电脑，今年售价5400元，比去年降低10%．去年售价多少元？(列方程解)
<gadget id="calculator">10 / 100</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">5_400 / (9/10)</gadget>
<output>6_000</output>

<result>6_000</result>