Given your experience as an organizational consultant, you have a client with a telephone company who
has requested that you help diagnose a potential problem at the telephone company. Your client explained
there has been a problem with a telephone line that is preventing customers from receiving or making
calls. The problem is disconcerting to both customers and the telephone company. You want to
understand the extent of the problem. Your client has provided you with preliminary data to examine. You
have a sample of 20 cases reported by two different offices of the telephone company.
Hint: If you follow the Pooled-Variance T.xls method to answer the questions, use Descriptive Statistics
in Data Analysis Toolpak to compute the sample mean, sample deviation, and sample size (i.e., count) for
each location OR use formulas to compute these measures in Microsoft Excel (i.e., =average, =stdev,
=count).
Once you compute the sample means, sample standard deviations, and sample sizes for each location,
enter these data into the Pooled-Variance T.xls file to compute statistics.
Central Office 1 Time to Clear Problems (minutes)
1.48 1.75 0.78 2.85 0.52 1.60 4.15 3.97 1.48 3.10
1.02 0.53 0.93 1.60 0.80 1.05 6.32 3.93 5.45 0.97
Central Office 2 Time to Clear Problems (minutes)
7.55 3.75 0.10 1.10 0.60 0.52 3.30 2.10 0.58 4.02
3.75 0.65 1.92 0.60 1.53 4.23 0.08 1.48 1.65 0.72

1. Assuming that the population variances from both offices are equal, construct and interpret a 95%
confidence interval estimate of the difference between the population means in the two offices.
2. Given your initial analysis of the data, do you believe a problem exists at the client facility that
requires further examination? If so, what additional data would you need to analyze to understand
the nature of the problem? Be specific in your explanations. (200-250 words).