The exponential function f(x)=42.2(1.56)^x models the average amount spent, f(x), in dollars, at a shopping mall after x hours. What is the average amount spent, to the nearest dollar, after four hours?

The exponential function f(x)=42.2(1.56)^x models the average amount spent, f(x), in dollars, at a shopping mall after x hours. What is the average amount spent, to the nearest dollar, after four hours?

Question
Exponential models
asked 2021-03-11
The exponential function \(f(x)=42.2(1.56)^x\) models the average amount spent, f(x), in dollars, at a shopping mall after x hours. What is the average amount spent, to the nearest dollar, after four hours?

Answers (1)

2021-03-12
Consider the given exponential function:
\(f(x)=42.2(1.56)^x\)
Where, f (x) is the average amount spent in dollars.
To Find:
The average amont spent after four hours:
Substitute \(x=4\):
\(f(4)=42.2(1.56)^4\)
\(f(4)=42.2(5.92240896)\)
\(f(4)=249.9256\)
\(f(4)\approx250\)
Hence, the average amount spent after four years is $250.
0

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