$$\frac{178}{706} \times 100 \approx 25.21\%$$

$$\frac{14}{50} \times 100 = 28\%$$

Question 1

Which of the following best describes the main steps in the statistical investigation cycle as shown in the first image?

Accepted Answer

Formulating questions, collecting data, organizing and summarizing data, making conclusions

Question 2

In the second image, which variables are considered quantitative?

Accepted Answer

Age, Weight, Height

Question 3

Given the third image, what type of data storage format is being used?

Accepted Answer

Unstacked data

Question 4

Using the frequency table in the fourth image, what is the total number of individuals represented?

Accepted Answer

$$325 + 285 + 706 + 885 = 2201$$

Question 5

Based on the relative frequency table in the fifth image, which class had the highest percentage?

Accepted Answer

Crew

Question 6

From the two-way table in the seventh image, what percentage of third class passengers survived?

Accepted Answer

$$\frac{178}{706} 	imes 100 \approx 25.21\%$$

Question 7

Why is it more appropriate to use percentages or rates rather than counts when comparing groups of different sizes?

Accepted Answer

Percentages and rates account for differences in group sizes, allowing for fair comparisons.

Question 8

In the ninth image, what is the percentage of mice that developed tumors in the LL group?

Accepted Answer

$$\frac{14}{50} 	imes 100 = 28\%$$

Question 9

Which of the following statements about the study in the ninth image is correct?

Accepted Answer

It is a controlled experiment because mice were randomly assigned to groups.

Question 10

If a study finds an association between two variables, what can be concluded?

Accepted Answer

Association does not imply causation; further investigation is needed to establish causality.

Question 11

Which of the following is a confounding variable in a study examining the relationship between exercise and weight loss?

Accepted Answer

Diet, because it can affect weight loss independently of exercise.

Question 12

What is the main advantage of random assignment in controlled experiments?

Accepted Answer

It minimizes bias and helps ensure groups are comparable.

Question 13

Why is a double-blind study considered the gold standard in experimental design?

Accepted Answer

It prevents both participant and researcher bias.

Question 14

Which of the following is an example of coding categorical data with numbers?

Accepted Answer

Assigning 1 for 'Yes' and 0 for 'No' in a survey question.

Question 15

A researcher wants to compare the rate of injuries in basketball and football. Which formula should be used to calculate the rate per 1,000 players?

Accepted Answer

$$	ext{Rate} = \frac{	ext{Number of Injuries}}{	ext{Number of Players}} 	imes 1000$$

Question 16

In a study, the outcome variable is whether a patient recovers from an illness. What is the treatment variable?

Accepted Answer

The specific medication or therapy given to the patient.

Question 17

Which of the following is NOT a reason why anecdotal evidence is unreliable for scientific conclusions?

Accepted Answer

It is always collected using random assignment.

Question 18

If a frequency table shows the counts for each category, what does a relative frequency table show?

Accepted Answer

The percentage of the total for each category.

Question 19

In the study of light exposure on mice (ninth image), can we conclude that 24 hours of light causes an increase in tumors? Why or why not?

Accepted Answer

Yes, because random assignment and control groups were used, reducing confounding variables.

Introduction to Data and Statistical Thinking

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