10 liters of oil are poured out (1/10), pouring out (1/10) liters, how many liters are left
10升油倒出(1/10)，在倒出(1/10)升，还剩多少升
<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">10 * (9/10)</gadget>
<output>9</output>

<gadget id="calculator">9 - (1/10)</gadget>
<output>89/10 = around 8.9</output>

<result>89/10 = around 8.9</result>