Question 1

A researcher collects the heights (in centimeters) of every student in a university. Is this data set a population or a sample?

Accepted Answer

Population

Question 2

A survey of 50 randomly selected patients at a hospital finds that the average waiting time is 18 minutes. Is this value a parameter or a statistic?

Accepted Answer

Statistic

Question 3

Which of the following is an example of qualitative data?

Accepted Answer

The favorite color of each employee in a company

Question 4

Which of the following is a discrete quantitative variable?

Accepted Answer

The number of cars sold by a dealership in a month

Question 5

A company wants to know if a new training program increases employee productivity. They randomly assign half of their employees to the new program and the other half to continue as usual, then compare productivity after one month. What type of study is this?

Accepted Answer

Experiment

Question 6

A nutritionist records the daily calorie intake of 100 randomly selected adults to study eating habits. Can the nutritionist conclude that a specific diet causes weight loss based on this data?

Accepted Answer

No, because this is an observational study and does not establish causation

Question 7

Which of the following best describes a representative sample?

Accepted Answer

A sample that reflects the characteristics of the entire population

Question 8

A school principal wants to survey teachers about a new policy. She randomly selects 5 teachers from each grade level. Is this a simple random sample?

Accepted Answer

No, because the sample is stratified by grade level

Question 9

Which of the following is NOT an example of quantitative data?

Accepted Answer

The brands of smartphones owned by students

Question 10

A city council wants to estimate the average commute time for all workers in the city. They randomly select 200 workers and find their average commute time is 32 minutes. Which of the following statements is correct?

Accepted Answer

32 minutes is a statistic for the sample

Question 11

A researcher wants to determine if a new medication reduces blood pressure. She gives the medication to one group and a placebo to another, then compares the results. What is the main advantage of this experimental design?

Accepted Answer

It allows for the establishment of causation

Question 12

Which of the following best describes a simple random sample?

Accepted Answer

A sample where every possible subset of the population has an equal chance of being selected

Question 13

A study measures the time (in seconds) it takes for swimmers to complete a lap. What type of data is this?

Accepted Answer

Quantitative, Continuous

Question 14

A university wants to know the average GPA of all its students. They survey 500 students and find an average GPA of 3.2. What is the population in this scenario?

Accepted Answer

All students at the university

Question 15

A store manager wants to know if extending store hours increases profits. She randomly selects half the stores to stay open later and compares profits at the end of the month. What type of study is this, and can causation be inferred?

Accepted Answer

Experiment; Yes, causation can be inferred

Question 16

Which of the following is an example of continuous quantitative data?

Accepted Answer

The time (in minutes) it takes to complete a survey

Question 17

A researcher surveys the eye color of 200 people. What type of data is being collected?

Accepted Answer

Qualitative

Question 18

A college professor wants to select a simple random sample of 5 students from a class of 20. Which of the following is the best method?

Accepted Answer

Assign each student a number from 1 to 20 and use a random number generator to select 5 unique numbers

Question 19

A study finds that 46.5% of all registered voters in a country are registered democrats. Is this value a parameter or a statistic?

Accepted Answer

Parameter

Question 20

A gym surveys 40 members and finds the average workout duration is 52 minutes. Is this value a parameter or a statistic?

Accepted Answer

Statistic

Introduction to Statistics: Populations, Samples, Data Types, and Sampling Methods

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