Answer Happy

(6) The following are the amount of time, in minutes, that it took a random sample of 20 technicians to perform a certain task: 18.1 20.3 18.3 15.6 22.5 16.8 16.8 17.6 17.6 16.9 18.2 19.3 16.5 19.5 18.6 20.0 18.8 19.1 17.5 18.5 17.0 18.0 Assuming that the sample came from a symmetric continuous distribution, use the sign test at the 0.05 level of significance to test the null hypothesis that the mean of the population is 19.4 against a 2-sided alternative. Perform the test using: (a) the binomial distribution; (b) the normal approximation to the binomial distribution.