Number of Jobs A sociologist found that in a sample of 57 retired men, the average number of jobs they had during their lifetimes was 7.3. The population standard deviation is 2.1. Use a graphing calculator and round the answers to one decimal place. Part: 0 / 4 Part 1 of 4 The best point estimate of the mean is

one z-score unit is equivalent to ______ of the distribution.  a. the variance b. the range c. the standard deviation d. the mean e. the correlation coefficient

Refer to the data set in the accompanying table. Assume that the paired sample data is a simple random sample and the differences have a distribution that is approximately normal. Use a significance level of 0.05 to test for a difference between the weights of discarded paper (in pounds) and weights of discarded plastic (in pounds). E Click the icon to view the data. In this example, Hg is the mean value of the differences d for the population of all pairs of data, where each individual difference d is defined as the weight of discarded paper minus the weight of discarded plastic for a household. What are the null and alternative hypotheses for the hypothesis test? O A. Ho: Ha = 0 H,: Ha #0 O B. Ho: Ha #0 H1: Hd =0 O C. Ho: Ha #0 O D. Ho: Ha = 0 H1: Hd 0

One hundred teachers attended a seminar on mathematical problem solving. The attitudes of representative sample of 12 of the teachers were measured before and after the seminar. A positive number for change in attitude indicates that a teacher's attitude toward math became more positive. The twelve change scores are as follows. 4; 7; −1; 1; 0; 5; −2; 2; −1; 6; 5; −3 Part (a) What is the mean change score? (Round your answer to two decimal places.)

What was the age distribution of prehistoric Native Americans? Extensive anthropological studies in the southwestern United States gave the following information about prehistoric extended family group of 96 members on what is now a Native American reservation. For this community, estimate the mean age expressed in years, the sample variance, and the sample standard deviation. For the class 31 and over, use 35.5 as the class midpoint. (Round your answer to one decimal place.) Average range(years) 1-10 11-20 21-30 31 and over   # of individuals  36 22 24 14   Mean=S2= S=

In a normal curve, the percentage of the scores between one and two standard deviations above the mean is approximately __________.   Select one: a. 14% b. 50% c. It is impossible to tell. d. 2% Clear my choice

What was the age distribution of prehistoric Native Americans? Extensive anthropological studies in the southwestern United States gave the following information about prehistoric extended family group of 85 members on what is now a Native American reservation. For this community, estimate the mean age expressed in years, the sample variance, and the sample standard deviation. For the class 31 and over, use 35.5 as the class midpoint. (Round your answer to one decimal place.) Average range(years) 1-10 11-20 21-30 31 and over   # of individuals  35 23 16 11   Mean=S2= S=

2b please

Which is NOT a correct statement about mean, median, standard deviation, or interquartile range?   a. Mean is more affected by changes in extreme observations   b. Median is less affected by changes in extreme observations   c. Standard deviation is less affected by changes in extreme observations   d. Interquartile range is less affected by changes in extreme observations

Gabriel and Lucia took a road trip across the country. The room costs, in dollars, for their overnight stays are listed in the accompanying table. How many of the cost amounts are within one standard deviation of the mean? Click the icon to view the room costs in dollars. There are cost amounts within one standard deviation of the mean. (Type a whole number.) Room Costs ($) 70 100 140 185 195 200 215 220 225 290 310 315 D -