Answer: The required average is $576.
Step-by-step explanation:
Since we have given that
Percent of customers not returning each year = 25%
Average customer lifetime = 
Percent of margin on the average bill = 60%
Cost per visit = $12
Number of times each year visited = 20 times
So, Average expense by each customer per year = 
Average margin = 60% of 240 = 
Average non discounted gross profit during a customer's lifetime is given by

Hence, the required average is $576.
Answer:
V = 15 in.³
Step-by-step explanation:
The original cylinder has radius r and height h.
V = πr²h
Its volume is 30 in.³, so
πr²h = 30 in.³
The new cylinder has radius (1/2)r and height 2h.
Its volume is
V = π(r/2)²(2h)
V = πr² × 2h/4
V = πr²h/2
πr²h is the volume of the original cylinder, and it is 30 in.³.
V = 30 in.³/2
V = 15 in.³
Answer:
21:18
Step-by-step explanation: