Respuesta :
Answer:
a. The mean of the net gain Danica receives if she buys a membership card is $5.
b. The standard deviation of the net gain Danica receives if she buys a membership card is $8.
Step-by-step explanation:
Price of a membership card per year = $25
Discount on each car wash purchased during the year = $2
Mean of the number of times Danica washes her car = 15
Standard deviation of the number of times Danica washes her car = 4
a. Calculation of the mean of the net gain Danica receives if she buys a membership card
Mean of the net gain = (Discount on each car wash purchased during the year * Mean of the number of times Danica washes her car) - Price of a membership card per year .............. (1)
Substituting the values into equation (1), we have:
Mean of the net gain = ($2 * 15) - $25 = $30 - $25 = $5
b. Calculation of the standard deviation of the net gain Danica receives if she buys a membership card
Standard deviation of the net gain = Discount on each car wash purchased during the year * Standard deviation of the number of times Danica washes her car .......................... (2)
Substituting the values into equation (2), we have:
Standard deviation of the net gain = $2 * 4 = $8
Conclusion
The mean of the net gain Danica receives if she buys a membership card is $5, and the standard deviation of the net gain Danica receives if she buys a membership card is $8.
