Question 1193014
a. phat = 0.25 It's the best guess there is.
b. this is sqrt (0.25*0.75/100)=0.0433
c. 80% half-interval is 1.28(0.0433)  using abs z(0.10). This is 0.056
The interval is (0.194, 0.306)
d. would be included in about 80 intervals. We wouldn't know which 80 of course.