If the sum of addition, subtraction, division, sum, difference, and quotient of a number and itself is 8.6, then what is this number?
一个数与自己相加、相减、相除、其和、差、商相加的和是8.6，那么这个数是多少．
<gadget id="calculator">8.6 - 1</gadget>
<output>7.6</output>

<gadget id="calculator">7.6 / 2</gadget>
<output>3.8</output>

<result>3.8</result>