Solution: We are given:

We need to find the z value corresponding to probability 0.84, in order to find the how much money almost 84% of gamblers spent at casino.
Using the standard normal table, we have:

Now we will use the z score formula to find the required amount:





approximately
Therefore, almost 84% of gamblers spent more than $720 amount of money at this casino.
Solve first for the solution of the inequalities. This can be done by replacing first the inequalities sign with the equal sign.
x + y = 1
2y = x - 4
The values of x and y from the system of linear equation are 2 and -1. This means that the intersection of the lines should be at point (2, -1).
Substitute 3 to x and determine the value of y from the second inequality.
2y ≥ x - 4
Substituting,
2y ≥ 3 - 4, y ≥ -1/2
Hence, the solution to this item should be the fourth one.
Mean 6.6
Median 6
Mode 3
Range 10
not positive on the 6.6 but the rest should be good