A college fund of $10,000 is set up with an annual interest rate of 4%, compounded annually. How many years will it take for the fund to reach $15,000? Use the formula A=P(1+nr)nt, where A is the balance (final amount), P is the principal (starting amount), r is the interest rate expressed as a decimal, n is the number of times per year that the interest is compounded, and t is the time in years. Round your answer to the nearest hundredth.
Q. A college fund of $10,000 is set up with an annual interest rate of 4%, compounded annually. How many years will it take for the fund to reach $15,000? Use the formula A=P(1+nr)nt, where A is the balance (final amount), P is the principal (starting amount), r is the interest rate expressed as a decimal, n is the number of times per year that the interest is compounded, and t is the time in years. Round your answer to the nearest hundredth.
Identify Values: Identify the values of P, r, n, and A. P=10000r=0.04n=1A=15000
Use Formula and Solve: Use the formula A=P(1+nr)nt and solve for t. 15000=10000(1+0.04)t
Divide and Simplify: Divide both sides by 10000. 1.5=(1.04)t
Take Natural Logarithm: Take the natural logarithm (\ln) of both sides to solve for t. ln(1.5)=ln((1.04)t)
Apply Logarithm Property: Use the property of logarithms: ln(ab)=b⋅ln(a). ln(1.5)=t⋅ln(1.04)
Isolate t: Divide both sides by ln(1.04) to isolate t. t=ln(1.04)ln(1.5)
Calculate t: Calculate the value of t. t≈ln(1.04)ln(1.5)t≈0.0392210.405465t≈10.34
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