设$$x=7$$，下面哪个最小？  最小的分数形式是$$b$$，其中$$b$$大于$$a$$．  在这个问题中，我们需要所有给定值中的最大可能值以分母表示．这个值是$$x+1$$或8  分子越小，就是$$6$$．  带有$$\frac {6}{x+1}$$的答案选项是$$\rm B$$．  为每个答案选项代入$$x$$会给出  ($$\rm A$$)$$\frac 67$$ ($$\rm B$$)$$\frac 68$$ ($$\rm C$$)$$\frac 66$$ ($$\rm D$$)$$\frac 76$$ ($$\rm E$$)$$\frac 86$$  从这里，我们可以看到最小的是答案选项$$\rm B$$．  The smallest fraction would be in the form $$\frac{a}{b}$$ where $$b$$ is larger than $$a$$.  In this problem, we would need the largest possible value out of all the given values to be in the denominator. This value is $$x+1$$ or $$8$$.  The smaller would go on the numerator, which is $$6$$.  The answer choice with $$\frac{6}{x+1}$$ is $$\text{B}$$.  Plugging $$x$$ in for every answer choice would give  ($$\rm A$$)$$\frac 67$$ ($$\rm B$$)$$\frac 68$$ ($$\rm C$$)$$\frac 66$$ ($$\rm D$$)$$\frac 76$$ ($$\rm E$$)$$\frac 86$$  From here, we can see that the smallest is answer choice $$\text{B}$$. 
对于$$x=7$$，以下哪一项是最小的？．
Options:
[1] $$\frac 6x$$ 
[2] $$\frac 6{x+1}$$ 
[3] $$\frac 6{x-1}$$ 
[4] $$\frac x6$$ 
[5] $$\frac {x+1}6$$ 