Arundel Company uses percentage of sales to estimate uncollectibles.  At the end of the fiscal year, December 31, 2018, Accounts Receivable has a balance of $78,000 and had a total of $875,000 in credit sales. Arundel assumes that 1.5% of sales will eventually be uncollectible. before adjustment, the Allowance for Uncollectible Accounts had a credit balance of 4,500. What dollar amount should be credited to Allowance for Uncollectible Accounts at year end?

4) The Chronicle of Higher Education (2009-2010 issue) published the accompanying data on the percentage of the population with a bachelor’s or higher degree in 2007 foreach of the 13 provinces or territories of Canada.

21 27 26 19 30 35 35 26 47 26 39 29 22

(a) Calculate these numerical summaries:

The median:

The interquartile range:

(b) Construct a box plot for these data.

What percentage of the area under the standard normal curve falls between z = - 0.51 and z = 0

Hockey - Birthdays: It has been observed that a large percentage of professional hockey players have birthdays in the first part of the year. It has been suggested that this is due to the cut-off dates for participation in the youth leagues - those born in the earlier months are older than their peers and this advantage is amplified over the years via more opportunities to train and be coached. Of the 510 professional hockey players in a season, 159 of them were born in January, February, or March.

(a) Assume that 25% of birthdays from the general population occur in January, February, or March (these actually contain 24.7% of the days of the year). In random samples of 510 people, what is the mean number of those with a birthday in January, February, or March? Round your answer to one decimal place.
μ =

(b) What is the standard deviation? Round your answer to one decimal place.
σ =

(c) Now, 159 of the 510 professional hockey players were born in the first three months of the year. With respect to the mean and standard deviation found in parts (a) and (b) what is the z-score for 159? Round your answer to two decimal places.
z =

(d) If the men in the professional hockey league were randomly selected from the general population, would 159 players out of 510 be an unusual number of men born in the first 3 months of the year?

Yes, that is an unusual number.No, that is not unusual.     

(e) Which of the following is an acceptable sentence to explain this situation?

If the men in the professional hockey league were selected randomly from the general population, this would be an unusual collection of birth dates.There is good reason to believe that a significantly larger than expected proportion of professional hockey league players are born in the first three months of the year.     This could be a result of the random variation of birth dates within a sample. However, it would be pretty unlikely to happen by chance.All of these are valid statements.

Let x be a random variable representing percentage change in neighborhood population in the past few years, and let y be a random variable representing crime rate (crimes per 1000 population). A random sample of six Denver neighborhoods gave the following information.

In this setting we have Σx = 73, Σy = 597, Σx² = 1457, Σy² = 73,973, and Σxy = 9938.

What percentage of variation in y is explained by the least-squares model? (Round your answer to one decimal place.)

Find or estimate the P-value of the test statistic.

P-value > 0.2500.125 < P-value < 0.250    0.100 < P-value < 0.1250.075 < P-value < 0.1000.050 < P-value < 0.0750.025 < P-value < 0.0500.010 < P-value < 0.0250.005 < P-value < 0.0100.0005 < P-value < 0.005P-value < 0.0005

Conclusion

Reject the null hypothesis, there is sufficient evidence that ρ differs from 0.Reject the null hypothesis, there is insufficient evidence that ρ differs from 0.    Fail to reject the null hypothesis, there is sufficient evidence that ρ differs from 0.Fail to reject the null hypothesis, there is insufficient evidence that ρ differs from 0.

(e) For a neighborhood with x = 24% change in population in the past few years, predict the change in the crime rate (per 1000 residents). (Round your answer to one decimal place.)
crimes per 1000 residents

(f) Find S_e. (Round your answer to three decimal places.)
S_e =

(g) Find an 80% confidence interval for the change in crime rate when the percentage change in population is x = 24%. (Round your answers to one decimal place.)

(h) Test the claim that the slope β of the population least-squares line is not zero at the 1% level of significance. (Round your test statistic to three decimal places.)

t =

Find or estimate the P-value of the test statistic.

P-value > 0.2500.125 < P-value < 0.250    0.100 < P-value < 0.1250.075 < P-value < 0.1000.050 < P-value < 0.0750.025 < P-value < 0.0500.010 < P-value < 0.0250.005 < P-value < 0.0100.0005 < P-value < 0.005P-value < 0.0005

Conclusion

Reject the null hypothesis, there is sufficient evidence that β differs from 0.Reject the null hypothesis, there is insufficient evidence that β differs from 0.    Fail to reject the null hypothesis, there is sufficient evidence that β differs from 0.Fail to reject the null hypothesis, there is insufficient evidence that β differs from 0.

(i) Find an 80% confidence interval for β and interpret its meaning. (Round your answers to three decimal places.)

Interpretation

For every percentage point increase in population, the crime rate per 1,000 increases by an amount that falls outside the confidence interval.For every percentage point decrease in population, the crime rate per 1,000 increases by an amount that falls outside the confidence interval.    For every percentage point decrease in population, the crime rate per 1,000 increases by an amount that falls within the confidence interval.For every percentage point increase in population, the crime rate per 1,000 increases by an amount that falls within the confidence interval.

What cosmological observations suggest the presence of Dark Energy? What percentage of the energy density in the Universe is Dark Energy?

Answer ASAP: Probability and Statistics question

Assume that the helium porosity (in percentage) of coal samples taken from any particular seam is normally distributed, but neither the mean LaTeX: \muμ nor the variance LaTeX: \sigma^2σ 2 is known. Suppose that we are given a sample of 25 specimens from the seam, with average porosity 8.85 and standard deviation 0.75.

Answer the following questions:

(a) Construct a 98% confidence interval for LaTeX: \muμ. How large is the margin of error?

(b) Does the interval in part (a) contain the true value of LaTeX: \mu μ? Explain why.

(c) Would a 96% confidence interval based on the same sample be narrower or wider than the 98% confidence interval? You do not need to calculate it but be sure to explain your reasoning clearly.

The U.S. Census Bureau conducts annual surveys to obtain information on the percentage of the voting-age population that is registered to vote. Suppose that 700 employed persons and 300 unemployed persons are independently and randomly selected and that 500 of the employed persons and 200 of the unemployed persons have registered to vote. Can we conclude that the percentage of the employed workers (p1), who have registered to vote, exceeds the percentage of unemployed workers (p2), who have registered to vote?

1. What is the alternative hypothesis?

2. What is the estimated proportion of unemployed people who are registered to vote; that is, what is p-hat 2?

3.  If the significance level is 0.1, what is the critical z-value?

4. Assume that the calculated test statistic is 2.02 (use this value even if you found another value in your calculations). Then, what is the conclusion to the hypothesis test? Use the critical z-value from Question 3.

Data from the U.S. Federal Reserve Board on the percentage of disposable personal income required to meet consumer loan payments and mortgage payments for selected years are shown in the following table. What is the value of the correlation coefficient for this data set? (Give the answer to four decimal places.)
r =

In baseball, is there a linear correlation between batting average and home run percentage? Let x represent the batting average of a professional baseball player, and let y represent the player's home run percentage (number of home runs per 100 times at bat). A random sample of n = 7 professional baseball players gave the following information.

(a) Make a scatter diagram of the data.

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(b) Use a calculator to verify that Σx = 1.949, Σx² = 0.549, Σy = 30.0, Σy² = 148.36 and Σxy = 8.687.

Compute r. (Round your answer to three decimal places.)


As x increases, does the value of r imply that y should tend to increase or decrease? Explain your answer.

Given our value of r, y should tend to increase as x increases.Given our value of r, we can not draw any conclusions for the behavior of y as x increases.     Given our value of r, y should tend to remain constant as x increases.Given our value of r, y should tend to decrease as x increases.