A town has a population of 7000 and grows at 3.5% every year. To the nearest tenth of a year, how long will it be until the population will reach 9400 ?Answer:
Q. A town has a population of 7000 and grows at 3.5% every year. To the nearest tenth of a year, how long will it be until the population will reach 9400 ?Answer:
Determine growth type: Determine the type of growth. The town's population grows at a constant percentage rate each year, which indicates exponential growth.
Identify key values: Identify the initial population (P0), the growth rate (r), and the final population (P).P0=7000, r=3.5%, and P=9400.
Convert rate to decimal: Convert the growth rate from a percentage to a decimal. r=3.5%=0.035.
Set up growth formula: Set up the exponential growth formula. The formula for exponential growth is P=P0×(1+r)t, where P is the final population, P0 is the initial population, r is the growth rate, and t is the time in years.
Substitute values and solve: Substitute the known values into the formula and solve for t.9400=7000×(1+0.035)t.
Isolate exponential part: Divide both sides by 7000 to isolate the exponential part of the equation.70009400=(1+0.035)t.
Calculate left side: Calculate the left side of the equation. 9400/7000≈1.3429.
Take natural logarithm: Take the natural logarithm of both sides to solve for t.ln(1.3429)=ln((1+0.035)t).
Use logarithm property: Use the property of logarithms that ln(ab)=b⋅ln(a).ln(1.3429)=t⋅ln(1.035).
Solve for t: Divide both sides by ln(1.035) to solve for t.t=ln(1.035)ln(1.3429).
Calculate final value: Calculate the value of t using a calculator.t≈ln(1.035)ln(1.3429)≈8.8.
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