Respuesta :
Answer:
1) A = 0.79
B = 0.4708
2) CI = (0.7728, 0.8072)
3) CI = (0.4481, 0.4935)
b. It appears that the proportion of adults who feel this way in country A is more than those in country B.
Step-by-step explanation:
1) Sample proportions for both Population A and B
For country A:
Sample size,n = 1500
Sample proportion = [tex] \frac{1185}{1500} = 0.79 [/tex]
For Country B:
Sample size,n = 1302
Sample proportion = [tex] \frac{613}{1302} = 0.4708 [/tex]
2) Confidence interval for country A:
Given:
Mean,x = 1185
Sample size = 1500
Sample proportion, p = 0.79
q = 1 - 0.79 = 0.21
Using z table,
90% confidence interval, [tex] Z _\alpha /2 = 1.64 [/tex]
Confidence interval, CI:
[tex] \frac{p +/- Z_\alpha_/2}{\sqrt{(p * q)/n}} [/tex]
[tex] = \frac{0.79 - 1.64}{\sqrt{(0.79 * 0.21)/1500}}, \frac{0.79 + 1.64}{\sqrt{(0.79 * 0.21)/1500}} [/tex]
[tex] CI = (0.7728, 0.8072) [/tex]
3) Confidence interval for country A:
Given:
Mean,x = 613
Sample size = 1302
Sample proportion, p = 0.4708
q = 1 - 0.4708 = 0.5292
Using z table,
90% confidence interval, [tex] Z _\alpha /2 = 1.64 [/tex]
Confidence interval, CI:
[tex] \frac{p +/- Z_\alpha_/2}{\sqrt{(p * q)/n}} [/tex]
[tex] = \frac{0.4708 - 1.64}{\sqrt{(0.4708 * 0.5292)/1302}}, \frac{0.4708 + 1.64}{\sqrt{(0.4708 * 0.5295)/1302}} [/tex]
[tex] CI = (0.4481, 0.4935) [/tex]
From both confidence interval, we could see that that the proportion of adults who feel this way in country A is more than those in country B.
Option B is correct.