Hardness of water from two different water treatment facilities is investigated. Observed water hardness (in ppm) for a random sample of faucets is as follows:
Facility 1 63 57 58 62 66 58 61 60 55 62 59 60 58 Facility 2 69 65 59 62 61 57 59 60 60 62 61 66 68 66
Use α=0.05α=0.05.
(f) Construct a 95% confidence interval for the difference in the mean water hardness for part (a).
Round your answers to two decimal places (e.g. 98.76).
Enter your answer; confidence interval, lower bound ≤μ1−μ2≤≤μ1-μ2≤ Enter your answer; confidence interval, upper bound
(g) Construct a 95% confidence interval for the difference in the mean water hardness for part (c).
Round your answers to two decimal places (e.g. 98.76).
Enter your answer; confidence interval, lower bound ≤μ1−μ2≤≤μ1-μ2≤ Enter your answer; confidence interval, upper bound