You intend to estimate a population mean $\displaystyle \mu$ with the following sample.

49.5
43.1
53.6
26.4
47.4
33.3
59.4
23.2
21.8
29.5

You believe the population is normally distributed. Find the 80% confidence interval. Enter your answer as an open-interval (i.e., parentheses) accurate to twp decimal places (because the sample data are reported accurate to one decimal place).

80% C.I. =

Answer should be obtained without any preliminary rounding. However, the critical value may be rounded to 3 decimal places.