I was doing some problems on this .Can some one please help me with the following:
Here the given answer is that quantity B is grater than Quantity A. How is this obtained? Do we know anything about the two distributions whether they are normal or what?
Also in the question
how is the answer obtained? Is it by plugging in various values?
Answer on 15.
(A) If $x>0$ then inequality $\frac53x<x$ would allow us to conclude that $$\frac53<1$$ (dividing by positive $x$ is permitted and does not change the sign) which is not true.
So it cannot have positive solutions.
(B) We can rewrite this as $$x(x-1)(x+1)<0$$ Then $x$ is a solution of it if it makes an odd number of these $3$ factors negative and makes the others positive. Can you find a positive $x$ that does that? Can you find a negative $x$ doing so as well?
(C) if $x$ would be a solution of this inequality then: $$-6<-7$$ (found by subtraction of $x$ on both sides) which is not true.
So the inequality has no solutions at all.