Ed venture Time (EZ SAT MATH)

To determine if age and gender are related to pet ownership at his school, Mark selected a random sample of 50 male 14 - to 15 -year-old students from the school and a random sample of 60 female 17- to 18-year-old students from the school. For each student, he recorded the student's age, gender, and whether the student owned a pet. Which of the following provides the best explanation for why Mark cannot draw a valid conclusion from this study?

• The sample sizes are too small.

• The two samples are not of equal size.

• Mark will be unable to tell whether a difference in pet ownership is related to age because the two age groups are too close in age.

• Mark will be unable to tell whether a difference in pet ownership is related to gender because of the difference in age. Similarly, he will be unable to tell whether a difference in pet ownership is related to age.

In a study of 24 adults and 8 adolescents, all participants took an 8-week mindfulness seminar. After the seminar concluded, the participants reported improvement in stress-related symptoms. Based on the study, which of the following is the most appropriate conclusion?

• Participation in a mindfulness seminar improves stress-related symptoms but only in the participants of this study.

• Participation in a mindfulness seminar improves stress-related symptoms in all adults and adolescents.

• Participation in a mindfulness seminar improves stress-related symptoms in adults but not in adolescents because the sample size for adolescents is too small.

• No conclusion can be drawn from the study about the causal relationship between participation in a mindfulness seminar and stress-related symptoms because everyone in the study took the seminar.

A 52% 4.2%

B 48% 1.6% 

The results of two random samples of votes for a proposition are shown above. The samples were selected from the same population, and the margins of error were calculated using the same method. Which of the following is the most appropriate reason that the margin of error for sample A is greater than the margin of error for sample B? 

• Sample A had a smaller number of votes that could not be recorded. 

• Sample A had a higher percent of favorable responses. 

• Sample A had a larger sample size. 

• Smaller A had a smaller sample size. ​

An ecologist selected a random sample of 30 prairie dogs from a colony and found that the mean mass of the prairie dogs in the sample was 0.94 kilograms (kg) with an associated margin of error of 0.12 kg. Which of the following is the best interpretation of the ecologist's findings?

• All prairie dogs in the sample have a mass between 0.82 kg and 1.06 kg.

• Most prairie dogs in the colony have a mass between 0.82 kg and 1.06 kg.

• Any mass between 0.82 kg and 1.06 kg is a plausible value for the mean mass of the prairie dogs in the sample.

• Any mass between 0.82 kg and 1.06 kg is a plausible value for the mean mass of the prairie dogs in the colony.

The table shows the results of a poll. A total of 803 voters selected at random were asked which candidate they would vote for in the upcoming election. According to the poll, if 6,424 people vote in the election, by how many votes would Angel Cruz be expected to win?

• 163 

• 1,304

• 3,864

• 5,621 

A polling organization surveys 1,200 randomly selected voters about their preferred candidate in an upcoming election. The poll reports that 48% of respondents support Candidate A, with a margin of error of ±3%.

Which of the following is the best interpretation of the poll’s findings?

• The true percentage of all voters supporting Candidate A is exactly 48%.

• The percentage of voters supporting Candidate A is between 45% and 51%.

• Candidate A will win the election with at least 48% of the vote.

• The poll is unreliable because only 1,200 people were surveyed.