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Briefly explain the terms population, sample, representative sample, random sample, sampling with replacement, and sampling without replacement.

Explain whether each of the following constitutes data collected from a population or a sample. a. Opinions on a certain issue obtained from all adults living in a city. b. The price of a gallon of regular unleaded gasoline on a given day at each of 28 gas stations in the Miami, Florida, metropolitan area. c. Credit card debts of 100 families selected from a given city. d. The percentage of all U.S. registered voters in each state who voted in the 2012 Presidential election. e. The number of left-handed students in each of 50 classes selected from a given university.

Explain whether each of the following constitutes data collected from a population or a sample. a. The number of pizzas ordered on Fridays during 2012 at all of the pizza parlors in your town. b. The dollar values of auto insurance claims filed in 2012 for 200 randomly selected policies. c. The opening price of each of the 500 stocks in the S\&P 500 stock index on January 3, 2012 . d. The total home attendance for each of the 18 teams in Major League Soccer during the 2012 season. e. The living areas of 35 houses listed for sale on March 7,2012 in Chicago, Illinois.

Explain the meaning of an element, a variable, an observation, and a data set.

Explain the meaning of the following terms. a. Quantitative variable b. Qualitative variable \(\underline{\text { c. }}\) Discrete variable d. Continuous variable e. Quantitative data f. Qualitative data

Indicate which of the following variables are quantitative and which are qualitative. a. Number of persons in a family b. Color of a car c. Marital status of a person d. Time to commute from home to work e. Number of errors in a person's credit report

Classify the following as cross-section or time-series data. a. Average prices of houses in 100 cities b. Salaries of 50 employees c. Number of cars sold each year by General Motors from 1980 to 2012 d. Number of employees employed by a company each year from 1985 to 2012

The number of pizzas delivered to a college campus on six randomly selected nights is \(48,103,95\), 188,286, and 136, respectively. Let \(x\) denote the number of pizzas delivered to this college campus on any given night. Find: a. \(\Sigma x\) b. \((\Sigma x)^{2} \quad\) c. \(\Sigma x^{2}\)

A car was filled with 16 gallons of gas on seven occasions. The number of miles that the car was able to travel on each tankful was \(387,414,404,396,410,422\), and 414 . Let \(x\) denote the distance traveled on 16 gallons of gas. Find: a. \(\Sigma x\) b. \((\Sigma x)^{2}\) c. \(\Sigma x^{2}\)

Indicate whether each of the following constitutes data collected from a population or a sample. a. A group of 25 patients selected to test a new drug b. Total items produced on a machine for each year from 1995 to 2012 c. Yearly expenditures on clothes for 50 persons d. Number of houses sold by each of the 10 employees of a real estate agency during 2012