Concept explainers
Reminder Round all answers to two decimal places unless otherwise indicated.
An Investment You have invested money in a savings account that pays a fixed monthly interest on the account balance. The following table shows the account balance over the first 5 months.
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a. How much money was originally invested?
b. Show that the data are exponential and find an exponential model for the account balance.
c. What is the monthly interest rate?
d. What is the yearly interest rate?
e. Suppose that you made this investment on the occasion of the birth of your daughter. Your plan is to leave the money in the account until she starts college at age 18. How large a college fund will she have?
f. How long does it take your money to double in value? How much longer does it take it to double in value again?
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Functions and Change: A Modeling Approach to College Algebra (MindTap Course List)
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