1. Math
2. Statistics And Probability
3. x 7 10 8 4 3 y 8 11 9...

# Question: x 7 10 8 4 3 y 8 11 9...

###### Question details
 x 7 10 8 4 3 y 8 11 9 5 4
 a. Calculate the covariance between the variables. (Negative value should be indicated by a minus sign. Round your intermediate calculations to 4 decimal places and final answer to 2 decimal places.)
 b-1. Calculate the correlation coefficient. (Round your intermediate calculations to 4 decimal places and final answer to 2 decimal places.)
 b-2. Interpret the correlation coefficient.
 There is _____ no, a weak negative, a weak positive, a strong negative, a perfect positive, a strong positive relationship between x and y.

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 The National Sporting Goods Association (NSGA) conducted a survey of the ages of individuals that purchased skateboarding footwear. The ages of this survey are summarized in the following relative frequency distribution. Assume the survey was based on a sample of 200 individuals.
 Age of User Percent Under 14 years old 23 14 to 17 years old 40 18 to 24 years old 18 25 to 34 years old 7 35 to 44 years old 7 45 to 64 years old 5
 Calculate the mean and the standard deviation of the age of individuals that purchased skateboarding shoes. Use 10 as the midpoint of the first class. (Do not round intermediate calculations. Round your answers to 2 decimal places.)
 Mean Variance Standard deviation

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 A manager of a local retail store analyzes the relationship between advertising and sales by reviewing the store’s data for the previous six months.
 Advertising (in $100s) Sales (in$1,000s) 205 129 56 44 55 43 54 42 169 139 203 127
 a. Calculate the mean of advertising and the mean of sales. (Round your answers to 2 decimal places.)
 Mean Advertising Sales
 b. Calculate the standard deviation of advertising and the standard deviation of sales. (Round your answers to 2 decimal places.)
 Standard Deviation Advertising Sales
 c-1. Calculate the covariance between advertising and sales. (Round your answer to 2 decimal places.)
c-2.

Interpret the covariance between advertising and sales.

 Positive correlation No correlation Negative correlation
 d-1. Calculate the correlation coefficient between advertising and sales. (Round your answer to 2 decimal places.)
d-2.

Interpret the correlation coefficient between advertising and sales.

 Weak positive correlation No correlation Strong negative correlation Weak negative correlation Strong positive correlation