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Consider the probability distribution shown below for the random variable X:                                                                                                     X             10           20           30           40           50           60      P (X)     0.05        0.20        0.30         0.25        0.10         0.10      Find the mean of this discrete probability distribution.

Suppose we want to estimate the average height of all young growing maple trees found on a certain nursery.  We select a random sample of 25 trees and measure their heights.  The sample mean is 75 inches and the sample standard deviation is 8 inches.  Construct a 90% confidence interval for the population mean (μ).  Assume that any necessary assumptions have been met.

The weights (in pounds) of a sample of 6 dogs are as follows: Dog Weight 1 30 2 32 3 26 4 42 5 40 6 46 Find the variance of the weights of this sample of 6 dogs.

Assume that we conduct an experiment using a randomized block design to determine the influece of 4 different diets on the weights of bison.  We group the blson into 10 blocks, where the bison within each of the 10 blocks have similar weights.  The partially completed Analysis of Variance table is shown below. Source          df        SS                MS                F Total             39      15,919.2 Diet                3         3.298.7 Block              9       12,073.9 Error             27            546.6                                Calculate the mean squares for blocks.

What are the 3 measures of central tendency?

A survey was conducted to determine how people rate the quality of programming available on TV.  Twenty-one respondents were asked to rate the overall quality from 0 (no quality at all) to 100 (extremely good quality). The stem-and-leaf display based on these data (using the first digit as the stem and the second digit as the leaf) is shown below: Stem                       Leaves                                     3               2     5 4               0     3     4     7     8     9 5               1     1     2     3     4     5 6               1     2     5     6     7 7               7     8 Based on the stem-and-leaf display, the upper quartile for these TV ratings is __________.

We want to test the following null and alternative hypotheses about a population proportion: Ho:  p = 0.70 Ha:  p  > 0.70 We observe 400 successes in a sample of 500 observations.  Assume that it is valid to use large-sample procedures in this problem. Calculate the test statistic needed to test the null hypothesis.  Should we reject or not reject Ho: p = 0.70 if we use a significance level of α = 0.05?  Explain.

Which one of the following confidence intervals would be the widest?

Consider the probability distribution shown below for the random variable X:                                                                                                     X             10           20           30           40           50           60      P (X)     0.05        0.20        0.30         0.25        0.10         0.10      Find the standard deviation of this discrete probability distribution.

A farm supply store manager wants to predict monthly sales, Y, for her company using advertising expenditures, X.  She has collected 10 months of data on past performance as shown in the following table. Advertising expenditures, in thousands of dollars, X Monthly sales, Y XY X2 Y2 1.2 101 121.2 1.44 10,201 0.8 92 73.6 0.64 8,464 1.0 110 110.0 1.00 12,100 1.3 120 156.0 1.69 14,400 0.7 90 63.0 0.49 8,100 0.8 82 65.6 0.64 6,724 1.0 93 93.0 1.00 8,649 0.6 75 45.0 0.36 5,625 0.9 91 81.9 0.81 8,281 1.1 105 115.5 1.21 11,025 TOTAL 9.4 959 924.8 9.28 93,569 The store manager performs a regression analysis and derives the following equation. Y =