The following exercise may be answered manually or with the assistance of a computer. Assume that the random variable is normally distributed. You may need to use the appropriate appendix table to answer this question.

A publisher of a crossword puzzle magazine wants to learn more about their customers. The publisher randomly sampled 13 customers and asked each how long does it take for them to successfully complete an average crossword puzzle. The times, in minutes, are listed next.

56

35

22

26

31

38

40

40

24

42

53

33

61

The publisher would like a 95% confidence interval estimate of the mean time, in minutes. (Round your answers to two decimal places.)