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The weights for newborn babies is approximately normally distributed with a mean of 5.1 pounds and a standard deviation of 1.1 pounds. Consider a group of 1300 newborn babies: 1. How many would you expect to weigh between 4 and 9 pounds? 2. How many would you expect to weigh less than 8 pounds? 3. How many would you expect to weigh more than 6 pounds? 4. How many would you expect to weigh between 5.1 and 10 pounds?

\begin{tabular}{l}\( \mid \) Which \( r \)-value implies the stronger linear relationship? Select one. \\ \( \square r=0 \) \\ \( \square r=-0.5 \) \\ \( \square r=-0.3 \) \\ \( \square r=-0.4 \) \\ \( \square r=-0.9 \) \\ \( \square r \) Question Help: \( \square \) Video \\ Submit Question \\ \hline\end{tabular}

(N) Gulliver tossed a coin 100 times and got 43 heads. What percent of the tosses were tails?

Ms Pitts has 220 students in her class. She would like to select a systematic sample of 20 students to answer a questionnaire. She numbers the students as they enter the lecture venue i.e. the \( 1^{\text {st }} \) student to enter gets assigned the number 1 , the \( 2^{\text {nd }} \) student to enter is assigned the number 2 etc. Ms Pitts randomly selects Student 10 to be the first student in her sample. Which student is the fourth to be selected for the sample? a) Student 11 b) Student 32 c) Student 43 d) Student 20 e) Student 30

Determine the minimum sample size required when you want to be \( 95 \% \) confident that the sample mean is within one unit of the population mean and \( \sigma=19.8 \). Assume the population is normally distributed. A \( 95 \% \) confidence level requires a sample size of (Round up to the nearest whole number as needed.)

In a survey of 2295 adults, 733 say they believe in UFOs. Construct a \( 99 \% \) confidence interval for the population proportion of adults who believe in UFOs. A \( 99 \% \) confidence interval for the population proportion is ( (Round to three decimal places as needed.) Interpret your results. Choose the correct answer below. B. With \( 99 \% \) confidence, it can be said that the population proportion of adults who believe in UFOs is between the endpoints of the given confidence interv C. The endpoints of the given confidence interval shows that \( 99 \% \) of adults believe in UFOs. D. With \( 99 \% \) probability, the population proportion of adults who do not believe in UFOs is between the endpoints of the given confidence interval.

In a survey of 3047 adults, 1459 say they have started paying bills online in the last year. Construct a \( 99 \% \) confidence interval for the population proportion. Interpret the results. A \( 99 \% \) confidence interval for the population proportion is (Round to three decimal places as needed.) Interpret your results. Choose the correct answer below. A. The endpoints of the given confidence interval show that adults pay bills online \( 99 \% \) of the time. B. With \( 99 \% \) confidence, it can be said that the sample proportion of adults who say they have started paying bills online in the last year is between the er the given confidence interval. C. With \( 99 \% \) confidence, it can be said that the population proportion of adults who say they have started paying bills online in the last year is between the endpoints of the given confidence interval.

The waiting times (in minutes) of a random sample of 20 people at a bank have a sample standard deviation of 4.1 minutes. Construct a confidence interval for the population variance \( \sigma^{2} \) and the population standard deviation \( \sigma \). Use a \( 95 \% \) level of confidence. Assume the sample is from a normally distributed population. What is the confidence interval for the population variance \( \sigma^{2} \) ? (Round to one decimal place as needed.) Interpret the results. Select the correct choice below and fill in the answer box(es) to complete your choice. (Round to one decimal place as needed.)

If all other quantities remain the same, how does the indicated change affect the minimum sample size requirement? (a) Increase in the level of confidence (b) Increase in the error tolerance (c) Increase in the population standard deviation (a) How does an increase in the level of confidence affect the minimum sample size requirement? Choose the correct answer below. (b) How does an increase in the error tolerance affect the minimum sample size requirement? Choose the correct answer below. An increase in the error tolerance (c) How does an increase in the population standard deviation affect the minimum sample size requirement? Choose the correct answer below. An increase in the population standard deviation

36. Los estudiantes en un curso de Matemáticas anotaron en el pizarrón el número de hermanos que tienen \( y \), al final, el profesor solicitó que obtuvieran el promedio. Las cantidades anotadas fueron: \( 3,5,0,5,2,1,1,2,3,0,1 \), ¿Cuál es el promedio?