Answer:
a) p = 0.1808
b) Since 341.54 ≥ 10. Therefore the requirements for constructing a confidence interval for p is satisfied.
c) The interval is (0.1676, 0.194)
d) We are 90% confident that the population proportion of adult Americans who have donated blood in the past two years is between 0.1676 and 0.194
Step-by-step explanation:
Given that:
n = 2306 and x =417
a) Obtain a point estimate for the population proportion (p) is the ratio of sample successes to sample size.
Therefore: p = x / n = 417 / 2306 = 0.1808
p = 0.1808
b) requirements for constructing a confidence interval for p is given by:
np(1-p) ≥ 10
Therefore: np(1-p) = 2306(0.1808)(1 - 0.1808) = 341.54 ≥ 10
Since 341.54 ≥ 10. Therefore the requirements for constructing a confidence interval for p is satisfied.
c) c = 90% = 0.9
α = 1 - 0.9 = 0.1
α / 2 = 0.1 /2 = 0.05
From the probability table, 
Margin of error (e) = 
The boundaries are (p - e, p + e) = (0.1808 - 0.0132, 0.1808 + 0.0132) = (0.1676, 0.194)
The interval is (0.1676, 0.194)
d) We are 90% confident that the population proportion of adult Americans who have donated blood in the past two years is between 0.1676 and 0.194
Remark
The best way to answer something like this is to actually graph both equations. I have done that for you below.
Red Line: f(x) = 1/4x - 1
Blue Line: g(x) = 1/2x - 2
Now look at the answers.
A: The first one is incorrect. You don't need the graph to tell you that. The larger the number in front of the x, the steeper the line. Put another way, the larger the slope, the steeper the line. The y intercept is lower however.
B is wrong. g(x) is steeper, but the y intercept is lower not higher than f(x) [Negatives do strange things].
C:The g(x) is steeper (we've said that a couple of times), and it has a lower y intercept.
D is correct.
E is just wrong. Both parts are incorrect.
49,98,147,196,245,294,343,392,441,490,539,588,637,686,735,784,833,882,931,980,1029,1078,1127,1176,1225,1274,1323,1372,1421,1470,1519,1568,1617,1666,1715,1764,1813,1862,1911,1960,2009,2058,2107,2156,2205,2254,2303,2352,2401,