We consider that the results obtained by the students in administrative sciences, for a test of aptitude in management computing, are distributed according to a normal distribution. For a random sample of 25 students, the mean score is 70.6 and the is 70.6 and the variance, s2 = 225 . Estimate by confidence interval, the upper limit of this interval for the average score of all students in administrative sciences with a confidence level of 90%. 74,55 78,99 75,06 75,73 76,79