Out of a sample of 150 people who walked into a fast food restaurant 135 said they prefer ketchup to mustard on their hamburgers. With 89% confidence, what is the confidence interval for the population mean of customers that prefer ketchup to mustard on their hamburgers? CI= (86. 09%, 93. 91%)
CI=(85. 20%, 94. 80%)
CI= (82. 61%, 95. 87%)
Cl = (83. 69%,96. 31)