Introductory statistics questions.

The ACME Company claims that their suitcases's average weight is 8 pounds. The Bell company thinks that ACME is lying and that ACME`S suitcases are heavier. Bell takes a random sample of 40 ACME suitcases and finds the average weight to be 9.3 pounds with a standard deviationof 3 pounds. Is there evidence to support Bell's claim at =0.01 ?, Justify.

Classify the variables as either categorical or numerical in each of the following, and if the variable is numerical classify it as either continuous or discrete.

1. A person`s height
2. An individual political affiliation
3. The number of rainy days in July
4. The number of gallons of fuel used to travel from Morogoro to DSM
5. A shoe size
6. An opinion to the question “Is the president of the United Republic of Congo doing good job?”

Identify the appropriate average to be used in each of the following cases

1. The size of shoes sold out in largest number from a shop
2. Average sales of various years
3. Estimation of intelligence of students in a class
4. Average rate of growth of population by decade
5. Average change in the cost of living of workers

An operator of a fleet of trucks purchases 100 tires(50 of Brand A and 50 of Brand B) at the same price. Under substantially similarity driving conditions, he gets the following results, the mean and standard deviation of tire Brand A were 16,000 miles and 4,000 miles respectively, for tire Brand B the mean and standard deviation were 20,000 miles and 8,000 miles respectively. Which brand you would advise him to buy in the future and why?

The values of two measures of central tendency are given bellow for three distributions . For each distribution  estimate whether it is approximately symmetrical, negative skewed or positive skewed. Assume each distribution is unimodal.

1. Mode=50, =58
2. Median=71.4, =71.4
3. Median=104,=796

Suppose you are given the following data,

  , , , and , where P= the predicator variable and Q= is the response variable.

1. Compute the correlation coefficient and coefficient of determination
2. Fit the regression line and state whether it is a good or poor fit.
3. Interpret the parameters of the model in part (b) above

Explain briefly the four measurement scales of variables.

Define the following terms

1. Mean
2. Median
3. Mode

Differentiate the following terms

1. Qualitative data and Quantitative data
2. Probability sampling and Non-probability sampling

The mean and standard deviation of a set of 100 observations were found to be 35 and 4 respectively. If the observations 39, 32 and 34 were omitted from the 100 observations, find the mean and standard deviation of the remaining 97 observations.