# Statistics

### Grumney Family Restaurant Ms. Brigden Tips – Solution Guide

At the time she was hired as a server at the Grumney Family Restaurant, Beth Brigden was told, “You can average \$70 a day in tips.” Assume the population of daily tips is normally distributed with a standard deviation of \$3.46. Over the first 32 days she was employed at the [...]Read more

### Normal Population Hypothesis Test

A sample of 33 observations is selected from a normal population. The sample mean is 30, and the  population standard deviation is 3. Conduct the following test of hypothesis using the 0.05 significance  level. H0 : μ<= 29 H1 : μ > 29 Setting up a Hypothesis Test in Excel [...]Read more

### Delivery time for all food orders at a restaurant during lunch hr are normally distributed…QNT 275

Quick Tutorial – Solving for Mean and Standard Deviation Delivery time for all food orders at a restaurant during lunch hr are normally distributed with a mean of 8.1 min and SD of 4.6 min let x bar be the mean delivery time for a random sample of 30 orders. Calculate the [...]Read more

### Statistical Communication for Rating, Ranking, Sorting Data

Choosing an Effective Communication Method for Statistical Studies The decision of an optimal communication method occurs when a researcher has determined the best data collection approach.  In the current business environment, technology has produced extensive changes to the [...]Read more

### Probability Sample Vs. Nonprobability Sample

Describe the differences between a probability sample and a nonprobability sample A probability sample collects and aggregates data is a way that is completely unbiased and not affected by subjective assumptions of the researchers. A true probability sample of American adults [...]Read more

### Pennsylvania Refining Company – Is the correlation in the population greater than zero?

Problem Overview In this tutorial, we are going to find out if the correlation in a sample population greater than zero using Excel.  Pennsylvania Refining Company is studying the relationship between the pump price of gasoline and the number of gallons sold. For a sample of 20 [...]Read more

### Maumee Ford-Mercury- Volvo Coefficient of Determination Solution

Problem Details The problem we are tackling in this tutorial is about car dealership data. We will show you how the find the Coefficient of Determination using Excel. The owner of Maumee Ford-Mercury- Volvo wants to study the relationship between the age of a car and its selling [...]Read more

### Bi-lo Appliance Super-Store Correlation Coefficient Solution

The famous Bi-Lo regression question goes something like this: Bi-lo Appliance Super-Store has outlets in several large metropolitan areas in New England. The general sales manager aired a commercial for a digital camera on selected local TV stations prior to a sale starting on [...]Read more

### Solve the Regression Equation for Random Observations

In this tutorial, we will use a series for random observations to perform a simple linear regression. The following sample observations were randomly selected. X 4 5 3 6 10 Y 9.8 12.6 9 14.4 19.6 Part A – The Regression Equation Regression Equation: Y = a + bX We can solve [...]Read more

### Celltronics Correlation Coefficient Solution

Correlation Coefficient The  correlation coefficient quantifies the relationship between two or more random variables. It can be calculated in MS Excel using the CORREL function, which we demonstrate below.  The production department of Celltronics International wants to explore [...]Read more