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First Question: The mean value of land and buildings per acre from a sample of f

ID: 3209269 • Letter: F

Question

First Question: The mean value of land and buildings per acre from a sample of farms is $1000,with a standard deviationof $200. The data set has a bell-shaped distribution.

a. Estimate the percent of farms whose land and building values per acre are between $600 and $800 OR greater than $1200 but less than $1400.

Second Question:

Suppose business has been good and the company gives every employee a $50 raise. List the new values of each summary statistic listed below:
lowest salary =
mean salary =
median =
range =
IQR =
first quartile =
standard deviation

3rd Question: A statistical analysis of 1000 long-distance phone calls made from the headquarters of the Bricks and Clicks Computer Corporation indicates that the length of these calls is normally distributed with a mean of 240 seconds and a standard deviation of 40seconds.

a. What % of these calls lasted less than 320 seconds?


b. What % of these calls lasted between the 2.5th and the 97.5th percentile?

c) What is the z-score value for a call that lasted 240 seconds?


d) What % of calls lasted less than 120 seconds or more than 320 seconds?

Explanation / Answer

mean = 100
Std Dev = 200

Let X = value of lands and buildings of farm per acre
P(600 < X < 800)
= P(600-1000/200 < Z < 800-1000/200)
= P(-2 < Z <- 1)

From the empirical rule, 13.5% of the farms have lands and buildings which are between $600 and $800 per acre.

P(1400 < X < 1200)
= P(1400-1000/200 < Z < 1200-1000/200)
= P(2 < Z <1)

From the empirical rule, 13.5% of the farms have lands and buildings which are between $1400 and $1200 per acre.

hope this will help you. Good luck:)