Blog

The mean length of time required to complete a 5K race was 20 minutes.  The standard deviation of the times was 4 minutes.  The racing times were approximately normally distributed.  What is the probability that a randomly selected runner completed the race in less than 16 minutes?

A Randomized Block Design is used to compare fleece weights of three breeds of sheep – Merino, Suffolk, and Dorset (we can think of the three breeds as being the three treatments).  The sheep are divided into two weight classes (i.e., two blocks).  Block one contains sheep weighing less than 150 lb and block two contains sheep weighing more than 150 lb.  The fleece weights (in pounds) are as follows:                    Merino          Suffolk          Dorset Block 1          13                  8                  9 Block 2          14                  9                 11                                                                          The partially completed ANOVA table for this experiment is as follows: Source     df          SS            MS            F      Total                29.33333 Breed              26.33333     13.16667    79.00003 Block                     Error                 0.33333        0.16667              The correct degrees of freedom for total, breed, block, and error, respectively are:

A randomized block design is used to compare litter sizes of the Yorkshire and Duroc breeds of sows.  Blocking is used in an attempt to remove the effects of sow age, since it is known that sow age influences litter size.  Each block contains sows of similar ages.  The data collected for this experiment are as follows:                   Yorkshire       Duroc       Block totals Block 1          9 pigs         7 pigs         16 pigs Block 2         10                8                18 Block 3         11                9                 20 Block 4         13              10                 23                                                                             Totals           43              34                 77   The partially completed ANOVA table for this experiment is as follows:   Source          df          SS          MS          F        Total                        23.875 Breed                      10.125      10.125      81.0 Block                       13.375       Error                          0.375                                   Calculate the mean square for blocks and the mean square for error.

Find the standard deviation of a binomial probability distribution with a sample size of n = 40 and a probability of success of 0.40.

Heights of 50 trees in a nursery are an example of a ____________ variable.

An experiment involves two factors, breed and diet, where there are 3 levels of diet and 4 levels of breed.  This experiment is referred to as a  __________.

Find the variance of a binomial probability distribution with a sample size of n = 40 and a probability of success of 0.40.

For small samples (n < 30), the sampling distribution of the sample mean depends on the particular form of the relative frequency distribution of the population being sampled.

Assume the mean length of time required to complete the Columbus Marathon was 4.5 hours and the standard deviation of the times was 0.70 hours.  Assume that the racing times were approximately normally distrubuted.  Only 10% of the runners would be expected to complete the race in less than x hours.  Find the value of x.

It is desired to estimate the average total compensation of CEO’s in the service industry.  Data were collected from 18 CEO’s and a 97% confidence interval was calculated to be ($2,181,260,  $5,836,180).  Which one of the following interpretations is correct?