By "the solution set of an inequality is x"

From "one of the inequalities needs to change the direction of inequality in the process of solving", we can know that the inequality group can be

( 1)-X & lt； =0 and x-8; =0 and 8-x > =0 has two groups.

X > is used to solve1; =0 and x

Solution 2 x >; =0 and-x > =-8 is X.

So the solution set is 0.

If there are ***x cars in total, the total * * is 4x+20 tons.

8x & gt4x+20

X> v

4x+20 & gt； 8(x- 1)

X< seven

5 & ltx & lt7。 And x is an integer, so x=6.

* * * A total of 6 cars.