The Average Lengths L of Cellular Phone Calls in Minutes

question 89

Multiple Choice

The average lengths L of cellular phone calls in minutes from 1999 to 2004 are shown in the table below. Use the regression feature of a graphing utility to find a linear model for the data. Let t represent the year, with t = 9 corresponding to 1999. Use the model to predict the average lengths of cellular phone calls for the year 2012. Round your answer to two decimal places.

• A) 5.00 minutes
• B) 8.00 minutes
• C) 4.00 minutes
• D) 2.00 minutes
• E) 3.00 minutes

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Definitions:

Fixed Costs

Fixed overheads, including rental costs, salary payments, and insurance fees, that stay unchanged with fluctuations in production or sales figures.

Required Units

The quantity of products or services that must be produced or sold to meet a specific target or fulfill a certain demand.

Variable Expenses

Costs that change in proportion to the activity or volume of operations in a business.

Net Income

The profit of a company after all expenses and taxes have been deducted from total revenue.