Homework Sourseconstruct a confidence interval of the population proportion
construct a confidence interval of the population proportion at the given level of confidence.
Solution
Answer to the question)
p = x/n
p = 175 /250
p = 0.7
.
SE = sqrt(p*(1-p)/n)
SE = sqrt(0.7*0.3/250)
SE = 0.02898
.
z value for 95% confidence level is 1.96
.
formula of confidence interval is:
p^ - z*SE , p^ + z* SE
0.7 -1.96 * 0.02898 , 0.7 + 1.96* 0.02898
0.6432 , 0.7568
