Exam 5: Approximating With a Distribution

Use the following to answer the questions below: Find the z* values based on a standard normal distribution for each of the following. Round to three decimal places. -An 86% confidence interval for a proportion.

Use the following to answer the questions below: Final grades in Professor Albert's large calculus class are approximately normally distributed with a mean of 76 (%) and standard deviation of 8 (%). -What proportion of students earn between an 82% and 88% in this class? Report your answer with three decimal places.

Use the following to answer the questions below: Robins are common birds in North America. Suppose that the wingspan of robins is approximately normal with mean 14 inches and standard deviation 0.7 inches. -What is the 30th percentile of robin wingspans? Report your answer with two decimal places.

Use the following to answer the questions below: A student suspects that the length of songs currently on her Spotify playlist are approximately normally distributed with a mean of 257 seconds and standard deviation 62 seconds. -The longest 25% of songs are longer than what length? Report your answer with one decimal place.

Use the following to answer the questions below: Use the provided density function to choose the best estimate for the proportion of the population found in the specified region. -The percent of the population that is more than 50 is closest to

Use the following to answer the questions below: A student suspects that the length of songs currently on her Spotify playlist are approximately normally distributed with a mean of 257 seconds and standard deviation 62 seconds. -The shortest 10% of songs are shorter than what length? Report your answer with one decimal place.

‪ -A biologist interested in estimating the correlation between the body mass (in grams) and body length (in cm) of porcupines has a random sample of 18 porcupines with The bootstrap distribution she constructed is approximately normal and the standard error is estimated to be 0.165. Use the normal distribution to construct and interpret a 98% confidence interval for the correlation between body mass and body length in porcupines. Round all values to three decimal places.

Use the following to answer the questions below: Select the answer closest to the specified areas for a N(0, 1) density. Round to three decimal places. -The area to the left of z = 0.63.

Use the following to answer the questions below: Robins are common birds in North America. Suppose that the wingspan of robins is approximately normal with mean 14 inches and standard deviation 0.7 inches. -The largest 20% of robins have wingspans longer than what value? Report your answer with two decimal places.

Use the following to answer the questions below: Use the provided density function to choose the best estimate for the proportion of the population found in the specified region. -The percent of the population between 20 and 80 is closest to

Use the following to answer the questions below: In the following, convert an area from one normal distribution to an equivalent area for a different normal distribution. Show details of your calculation. Draw sketches of both normal distributions, find and label the endpoints, and shade the regions on both curves. -The "Q1" for a standard normal distribution converted to a N(15, 2.5) distribution.

Use the following to answer the questions below: Find the endpoint(s) on the normal density curve with the given property. Round to three decimal places. -The area to the right of the endpoint on a N(26, 4) curve is about 0.4.

Use the following to answer the questions below: Robins are common birds in North America. Suppose that the wingspan of robins is approximately normal with mean 14 inches and standard deviation 0.7 inches. -What proportion of robins have wingspans less than 13 inches? Report your answer with three decimal places.

Use the following to answer the questions below: Robins are common birds in North America. Suppose that the wingspan of robins is approximately normal with mean 14 inches and standard deviation 0.7 inches. -What proportion of robins have wingspans longer 15.5 inches? Report your answer with three decimal places.

Use the following to answer the questions below: Select the answer closest to the specified areas for a N(0, 1) density. Round to three decimal places. -The area to the right of z = -0.47.

Use the following to answer the questions below: A student suspects that the length of songs currently on her Spotify playlist are approximately normally distributed with a mean of 257 seconds and standard deviation 62 seconds. -What proportion of songs are less than 180 seconds (3 minutes)? Report your answer with three decimal places.

Use the following to answer the questions below: Find the endpoint(s) on a N(0, 1) density with the given property. Round to three decimal places. -The area to the left of the endpoint is about 0.20.

Use the following to answer the questions below: Robins are common birds in North America. Suppose that the wingspan of robins is approximately normal with mean 14 inches and standard deviation 0.7 inches. -What proportion of robins have wingspans between 12.5 and 13.5 inches? Report your answer with three decimal places.

Use the following to answer the questions below: Heights of 10-year-old girls (5th graders) follow an approximately normal distribution with mean inches and standard deviation of inches. -What is the IQR of heights of 10-year-old girls? Note that you will need to find two endpoints of the distribution for your calculation. Report you answer with one decimal place.

Use the following to answer the questions below: Use the provided density function to choose the best estimate for the proportion of the population found in the specified region. -The percent of the population that is less than 20 is closest to