Precal 7.7a Test

The exponential function f(x) passes through the points (1, 5) and (4, 2). Find the equation for f(x).

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• no solution
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If you start with a 100 g sample of a radioactive isotope and in 10 days measure it to be 86.3 g. Find the equation for f(x).

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• 
• 
• 
• no solution

The exponential function f(x) passes through the points (1, 5) and (4, 2). Evaluate f(6).

• 1.086
• 0.9567
• 0.8633
• no solution
• 1.347

The exponential function f(x) passes through the points (1, 5) and (4, 2). What is the growth rate r(x)?

• -26.3%
• -13.3%
• -37%
• no solution
• 30.7%

The town of Lexington SC is growing at an average rate of 2.31%.If the town had a population of 23,568 in the year 2020 and the growth rate stays the same, how many do we predict it to have ten years later?

• 29,614
• 30,418
• 31,763
• no solution
• 23,957

The town of Lexington SC is growing at an average rate of 2.31%.If the town had a population of 23,568 in the year 2020 and the growth rate stays the same, how many do we predict it had 20 years ago?

• 14,927
• 10,311
• 12,456
• 13,865
• no solution

The town of Lexington SC is growing at an average rate of 2.31%.If the town had a population of 23,568 in the year 2020 and the growth rate stays the same, in what year will it reach a population of 100,000?

• 2083
• 2067
• 2056
• 2075
• 2103

If a town increased from 10,158 to 19,566 in 10 years of exponential growth, what is its average growth rate r(t)?

• 6.8%
• 4.3%
• 1.068
• 1.043
• 1.086

If you start with a 100 g sample of a radioactive isotope and in 10 days measure it to be 86.3 g. What is the half life of the isotope?

• 47.0 days
• 41.0 days
• 49.0 days
• 51.0 days
• 39.0 days

The population of rabbits on Dreher Island is being tracked by wildlife management every month. At time t = 0 the population was 2,150 rabbits and 4 months later the population was 2,650 rabbits. The population is growing exponentially and is given by P(t). What is the rate of growth in the rabbit population?

• 5.4%
• 5.1%
• 5.7%
• 4.9%
• 4.3 %