Answer:
i) Estimate the value of the population proportion = 0.8
ii) 95% confidence interval for the population proportion
(0.7214 , 0.8784)
iii) Lower bound = 0.7214
upper bound = 0.8784
Step-by-step explanation:
<u><em>Step(i):-</em></u>
Given sample size 'n' = 100
Given data he surveys 100 customers and finds that 80 paid at the pump
sample proportion
<u><em>Step(ii):-</em></u>
<u><em>95% confidence interval for the population proportion is determined by</em></u>
<u><em></em></u><u><em></em></u>
<em>Level of significance </em>
<em>∝ =0.05</em>
<em>Z₀.₀₅ = 1.96</em>
<em></em><em></em>
<em>On calculation , we get</em>
<em>(0.8 - 0.0784 , 0.8 + 0.0784)</em>
<em>(0.7214 , 0.8784)</em>
<u><em>Conclusion:</em></u><em>-</em>
95% confidence interval for the population proportion
(0.7214 , 0.8784)