Statistics and Confidence Intervals: Chapter 7 & 8

Flashcards for reviewing key concepts and calculations related to statistics, confidence intervals, and hypothesis testing.

What is the sample mean gas mileage for the new car in the study?

The sample mean gas mileage is 37.7 mpg.

What is the sample standard deviation of gas mileage for the new car?

The sample standard deviation is 4.22 mpg.

What is the confidence level for the gas mileage estimation in the new car study?

The confidence level is 95%.

In a national survey, what proportion of U.S. adults own a pet according to the findings?

1540 out of 2500 people own a pet.

At what confidence level is the proportion of U.S. adults who own a pet being estimated?

The confidence level is 90%.

What is the sample mean travel time for commuter students to campus?

The sample mean travel time is 19.4 minutes.

What is the population standard deviation for the commuter students' travel time?

The population standard deviation is 9.52 minutes.

What is the significance level for the hypothesis test regarding insurance claims?

The significance level is 0.05.

If the insurance company claims that 90% of claims are settled within a month, what was the sample size for testing this claim?

The sample size was 75 claims.

What is the sample mean weight of the plates being tested?

The sample mean weight is 24.605 pounds.

What is the claimed weight of the plates by the company?

The claimed weight is 25 pounds.

For the new strain of green beans, what is the sample mean maturity rate found by the farmer?

The sample mean maturity rate is 52 days.

What is the standard deviation of the maturity time for the new strain of green beans?

The standard deviation is 3.1 days.

What is the significance level for testing the claim about the maturity time of the green bean seeds?

The significance level is 0.05.

What error types should be reviewed in the context of hypothesis testing?

Type I and Type II errors.

What is the margin of error required for the university's new final exam confidence interval?

The margin of error needed is 2.5 points.