If for all b, define a△b=a*x, x is a constant that has nothing to do with b; define a▼b=(a+b)/2, and (1△3)▼3=1△(3▼ 3), then what is the value of (1△6)▼2.
若对所有b，定义a△b=a*x，x是一个与b无关的常数；定义a▼b=(a+b)/2，且(1△3)▼3=1△(3▼3)，那么(1△6)▼2的值是多少．
<gadget id="calculator">1 * 1.5</gadget>
<output>1.5</output>

<gadget id="calculator">1.5 + 2</gadget>
<output>3.5</output>

<gadget id="calculator">3.5 / 2</gadget>
<output>1.75</output>

<result>1.75</result>