You get paid on the first day of each month. You cash your check and pay all of your essential expenses. You keep the balance in your "discretionary spending" envelope. A scatter plot shows the number of days that have passed since you were paid and the amount left in your discretionary spending envelope. The explanatory x-variable is the number of days that have passed. The response y-variable is the amount left in your envelope. Is there a positive or negative correlation? Explain.

Jackie deposited a $865.98 paycheck, a$623 stock dividend check, a $60 rebate check, and$130 cash into her checking account. Her original account balance was $278.91. Assuming the checks clear, how much was in her account after the deposit was made?

The MyTunes song app sells music downloads. Over the past few years, the service has lowered its prices. The table shows the price per song and the number of songs downloaded per day at that price.

$$\begin{array}{|c|c|} \hline \text{Price per} & \text{Number of Downloads} \\ \text { Song } & \text { (in thousands) } \\ \hline \$ 0.89 & 1,212 \\ \$ 0.79 & 1,704 \\ \$ 0.69 & 1,760 \\ \$ 0.59 & 1,877 \\ \$ 0.49 & 1,944 \\ \$ 0.39 & 2,011 \\ \hline \end{array}$$

Examine the data without drawing a scatter plot. Describe any trends you see.

The MyTunes song app sells music downloads. Over the past few years, the service has lowered its prices. The table shows the price per song and the number of songs downloaded per day at that price.

$$\begin{array}{|c|c|} \hline \text{Price per} & \text{Number of Downloads} \\ \text { Song } & \text { (in thousands) } \\ \hline \$ 0.89 & 1,212 \\ \$ 0.79 & 1,704 \\ \$ 0.69 & 1,760 \\ \$ 0.59 & 1,877 \\ \$ 0.49 & 1,944 \\ \$ 0.39 & 2,011 \\ \hline \end{array}$$

Approximate the number of downloads at a price of $0.54 per song. Explain your reasoning.

MoviePlay is an online movie rental service. They have a sliding price list based upon the popularity of the movies. The table below shows the rentals by price category for the month of September. Let x represent the price and y represent the number of movies rented at that price. $$ \begin{matrix} \text{Price} & \text{# of rentals}\\ \text{5.99} & \text{800}\\ \text{4.99} & \text{1,000}\\ \text{3.99} & \text{1,200}\\ \text{2.99} & \text{1,380}\\ \text{1.99} & \text{1,672}\\ \text{0.99} & \text{1,903}\\ \end{matrix} $$ a. Examine the data without drawing a scatter plot. Describe any trends you see. b. Draw a scatter plot. Describe the correlation. c. Based on this information, how many rentals might be anticipated if the company instituted a new price category of $6.99. Explain your reasoning.

Describe each of the following correlation coefficients using the terms strong, moderate, or weak and negative or positive. a. $r=-0.19$, b. $r=-0.93$, c. $r=0.57$, d. $r=0.0999$, e. $r=-0.97$, f. $r=-0.45$.

Describe each of the following correlation coefficients using the terms strong, moderate, or weak and negative, or positive. r = 0.21

How do you say 'Yes, I am going to travel by plane. I go to the international airport (name of airport)' in Spanish?

A recent Internet survey showed per-day lodging expenses at Disney World in Orlando range from less than $100 for a campsite to more than$2,000 for a top luxury room. The cost-per-day average of the top 10 most popular hotels at Disney World is $348. If the standard deviation is$80, find the z-score for a per-day expense of $400.

Getaway Sports is a vacation destination for the serious sports fanatic. Rajesh is in charge of equipment for the complex. The last shipment of ping-pong balls was normally distributed with a mean weight of 2.7 grams and a standard deviation of 0.1 gram. The 100-pound weights he orders from the manufacturer for the fitness center are normally distributed with mean weight 100.2 pounds and standard deviation 0.1 pound. Which distribution is more dispersed? Explain.

Getaway Sports is a vacation destination for the serious sports fanatic. Rajesh is in charge of equipment for the complex. The last shipment of ping-pong balls was normally distributed with a mean weight of 2.7 grams and a standard deviation of 0.1 gram. The 100-pound weights he orders from the manufacturer for the fitness center are normally distributed with mean weight 100.2 pounds and standard deviation 0.1 pound. Which distribution has the larger standard deviation?

International travel is usually more expensive than domestic travel. A recent survey found that the average per-person cost of a 12-day international vacation is $1,755. This includes transportation, food, lodging, and entertainment. If the data are normally distributed with standard deviation$390, find the percentage of vacationers who spent less than $1,200 per day. Round to the nearest hundredth of a percent.

Describe the type of correlation indicated by each correlation coefficient. r= -0.19

The variance of a distribution is 195. What is the standard deviation, rounded to the nearest thousandth?