Guide to Using Minitab 14 For Basic Statistical

Guide to Using Minitab 14 For Basic Statistical Applications To Accompany Business Statistics: A Decision Making Approach, 7 th Ed. Chapter 6: Introduction to Continuous Probability Distributions By Groebner, Shannon, Fry, & Smith Prentice-Hall Publishing Company Copyright, 2008

Standard Normal State Bank and Trust Issue: State bank managers have studied the time customers spend at the bank on business. They plan to offer a gift certificate to any customer who is required to spend over 30 minutes on bank business. Objective: Use Minitab to analyze, create histogram and determine the probability that a certificate will be given to any customer. The data file is State Bank. MTW.

Standard Normal – State Bank and Trust Open Data File: State Bank. MTW

Select Graph - Histogram

Standard Normal – State Bank and Trust Select Simple

Standard Normal – State Bank and Trust Define variable to graph –Click OK

Standard Normal – State Bank and Trust Completed Histogram – next determine probability of a customer waiting over 30 minutes

Standard Normal – State Bank and Trust Select Calc – Probability Distribution - Normal

Standard Normal – State Bank and Trust Set to Cumulative Probability – Specify Mean and Standard Deviation and the input constant(x = 30 here)

Standard Normal – State Bank and Trust P(X <30) = 0. 9016 Then P (x > 30) = 1 - 0. 9016 = 0. 0984

Exponential Distribution Haines Internet Services Issue: The time between connect attempts averages two minutes and the distribution of time between attempts is assumed to be exponential. Objective: Use Minitab to compute the probability that the time between connect attempts will be less or equal to 45 seconds.

Exponential Distribution – Haines Internet Services Use Calc – Probability Distributions - Exponential

Exponential Distribution – Haines Internet Services Check Cumulative – Specify Mean = 2 seconds and define input constant ( 0. 75 here).

Exponential Distribution – Haines Internet Services Exponential Distribution Probability Result P(X < 0. 75 minutes) = 0. 3127