The average number of times Americans dine out in a week fell from 4.0 in 2008 to 3.8 in 2012 (Zagat.com, April 1, 2012). The number of times a sample of 20 families dines out last week provides the following data.

6             1              5              3              7              3              0              3              1              3

4              1              2              4              1              0              5              6              3              1

a)      The skewness measure for these data is 0.34. Comment on the shape of the distribution. Is it the shape you would expect? Why or Why not?

​b) Do the data contains outliers

3. A chemical engineer is studying the effects of temperature and catalyst on the percentage of undesired byproduct in the output of a chemical reactor. Orders of testing were determined using random numbers. Percentage of the byproduct is shown in the table below.

Catalyst Temperature, ~
#1 140 150
2.3 1.6
1.3 2.8
#2    3.6 3.0
3.4 3.8
The diagnostic plots recommended in part (c) of section 12.1 were carried out and showed no significant discrepancies. Can we conclude (at the 5% level of significance) that catalyst or temperature or their interaction affects the percent- age of byproduct?

1. In 2004, Murthy, Krumholz, & Gross investigated disparities in access to clinical trials in an article entitled “Participation in cancer clinical trials: race-, sex-, and age-based disparities”.

Does the distribution of participants in clinical trials correspond to the population distribution, given that…

a.

b.

3. What would you conclude based on these findings?

The table below shows the hours of relief provided by two analgesic drugs in 12 patients suffering from arthritis. Is there any evidence that one drug provides longer relief than the other? Use Wilcoxon Signed-RankTest.

Case    A         B

1          2.0       3.5

2          14.9     16.7

3          3.6       5.7

4          6.6       6.0

5          2.6       2.9

6          2.3       3.8

7          2.6       2.4

8          2.0       4.0

9          7.3       9.9

10        6.8       9.1

11        3.4       3.3

12        8.5       20.9

In the following problem, check that it is appropriate to use the normal approximation to the binomial. Then use the normal distribution to estimate the requested probabilities.

It is estimated that 3.8% of the general population will live past their 90th birthday. In a graduating class of 721 high school seniors, find the following probabilities. (Round your answers to four decimal places.)

(a) 15 or more will live beyond their 90th birthday


(b) 30 or more will live beyond their 90th birthday


(c) between 25 and 35 will live beyond their 90th birthday


(d) more than 40 will live beyond their 90th birthday

Calculate the molarity of a 1.8 L solution that contains 6.71 moles of NaCl. How many moles of NaOH are in a 935 mL solution that has a concentration of 7.3 M?

What is the volume (in L) of a solution that contains 3.8 moles of MgCl2 and has a concentration of 2.5 M? When you use 58.9 mL of 4.0 M HCl to produce H2 gas, how many grams of zinc does it react with? 2HCl + Zn → ZnCl2 + H2

How many moles of NaOH are in a 1438 mL solution that has a concentration of 1 M?

In the following problem, check that it is appropriate to use the normal approximation to the binomial. Then use the normal distribution to estimate the requested probabilities.

It is estimated that 3.8% of the general population will live past their 90th birthday. In a graduating class of 714 high school seniors, find the following probabilities. (Round your answers to four decimal places.)

(a) 15 or more will live beyond their 90th birthday


(b) 30 or more will live beyond their 90th birthday


(c) between 25 and 35 will live beyond their 90th birthday


(d) more than 40 will live beyond their 90th birthday

In the following problem, check that it is appropriate to use the normal approximation to the binomial. Then use the normal distribution to estimate the requested probabilities.

It is estimated that 3.8% of the general population will live past their 90th birthday. In a graduating class of 728 high school seniors, find the following probabilities. (Round your answers to four decimal places.)

(a) 15 or more will live beyond their 90th birthday

(b) 30 or more will live beyond their 90th birthday

(c) between 25 and 35 will live beyond their 90th birthday

(d) more than 40 will live beyond their 90th birthday

Interpret the slope by circling the correct answers and filling in the blanks. See pp. 194-195 in the course text.

“If the distance between the fire and nearest fire station [ increases | decreases ] by ___________ mile(s), the amount of damage [ increases | decreases ] by ___________ thousand dollars, on average.”