Refer to the accompanying data display that results from a simple random sample of times (minutes) between eruptions of the Old Faithful geyser. The confidence level of 95% was used.

TInterval

(85.74,91.76)

x=88.75

Sx=8.897431411

n=36

a. Express the confidence interval in the formula that uses the "less than" symbol. Round the confidence interval limits given that the original times are all rounded to one decimal place.

____min

b. Identify the best point estimate of u and the margin of error.