A new car is purchased for 16400 dollars. The value of the car depreciates at 6.75% per year. To the nearest year, how long will it be until the value of the car is 8500 dollars?Answer:
Q. A new car is purchased for 16400 dollars. The value of the car depreciates at 6.75% per year. To the nearest year, how long will it be until the value of the car is 8500 dollars?Answer:
Identify Depreciation Type: Determine the type of depreciation. The car depreciates at a constant percentage each year. This is an example of exponential decay.
Find Initial, Rate, Final Value: Identify the initial value a, the rate of depreciation r, and the final value P.(\newline\)Initial value a = $16,400(\newline\)Rate of depreciation r = 6.75% per year(\newline\)Final value P = $8,500
Convert Rate to Decimal: Convert the rate of depreciation to a decimal. r=6.75%=0.0675
Set Up Exponential Decay Formula: Set up the exponential decay formula.The formula for exponential decay is P=a(1−r)t, where P is the final amount, a is the initial amount, r is the rate of decay, and t is the time in years.
Substitute Values into Formula: Substitute the known values into the formula. 8500=16400(1−0.0675)t
Solve for t: Solve for t.First, divide both sides by 16400 to isolate the exponential expression.164008500=(1−0.0675)t0.5183≈(1−0.0675)t
Take Natural Logarithm: Take the natural logarithm of both sides to solve for t.ln(0.5183)≈ln((1−0.0675)t)
Use Logarithm Property: Use the property of logarithms that ln(ab)=b⋅ln(a).ln(0.5183)≈t⋅ln(1−0.0675)
Calculate Natural Logarithm: Calculate the natural logarithm of both sides.ln(0.5183)≈t×ln(0.9325)
Divide by Logarithm: Divide both sides by ln(0.9325) to solve for t.t≈ln(0.9325)ln(0.5183)
Calculate Value of t: Use a calculator to find the value of t.t≈ln(0.5183)/ln(0.9325)t≈−0.6561/−0.0693t≈9.47
Round to Nearest Year: Round t to the nearest year.t≈9 years
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