Susan bought a new car in 2020 for $48000. If the value of the car decreases by 11% each year write an exponential modle for the value of the car. Then, estimate the cost of the car in the year 2023.
Q. Susan bought a new car in 2020 for $48000. If the value of the car decreases by 11% each year write an exponential modle for the value of the car. Then, estimate the cost of the car in the year 2023.
Identify values: Identify the initial value a and the rate of decrease r. The initial value of the car, a, is $48,000. The car decreases in value by 11% each year, so r=−11% or −0.11.
Convert rate to factor: Convert the rate of decrease to the decay factor b. The decay factor b is calculated by subtracting the rate of decrease from 1. So, b=1−r. b=1−(−0.11)b=1+0.11b=1.11 This is incorrect because we should be subtracting the rate of decrease, not adding it. Let's correct this. b=1−0.11b=0.89
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