Answer:
1) p1=0.83
2) p2=0.81
3) Option B
4) p=0.82
5) s=0.03
6) z=0.67
7) P=0.50
8) Do not reject H0
Step-by-step explanation:
1) The proportion of Republicans who think the full-body scans should be applied in airports is equal to the ratio between the republicans that think it should over the total Republicans in the poll:

2) The proportion of Democrats who think the full-body scans should be applied in airports is equal to:

3) As we want to know if there is a difference in the proportions calculated, not if one is higher or lower than the other, the correct option is B:

4) The pooled estimate of a proportion is the average of both proportions:

5) The standard error can be calculated as:

6) The z-statistic can be calculated as:

7) The P-value for z=0.67 is P=0.50 (from the standard normal distribution table).

8) If the significance level is 0.01, the P-value is bigger than the significance level. The effect is not significanct. The null hypothesis is not rejected.
There is not enough evidence to say that both proportions are different.
A. Do not reject H0
Answer:
x=0, x=-4
Step-by-step explanation:
Answer:
The problem is stated as:
Min C = 15*(2*x +y) + 21*y
subject to x*y = 450
Step-by-step explanation:
Given that the region is rectangular, it has two opposite sides called x and two other opposite sides called y (both measured in feet). Then, the area (in square feet) is:
A = x*y = 450
One of the sides called y costs $21 per linear foot. The other 3 sides (two x and one y) costs $15 per linear foot. Then, the cost function is:
C = 15*(2*x +y) + 21*y
For part A Amy's estimate is inaccurate because when adding fractions they must have the same denominators. Amy probably made the mistake of adding 1/4 and 1/3 without changing the denominators first which gave her 1/7. If she were to do it correctly then she would've ended up with 7/12 as her answer.
My work:
1/4=3/12
1/3=4/12
4/12+3/12=7/12
I hope this helps and if I gave any false information I apologize in advance.