You put $8,000 into a savings account that has an annual interest rate of 3%, compounded annually. How many years will it take for your savings to increase to $12,000? 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. You put $8,000 into a savings account that has an annual interest rate of 3%, compounded annually. How many years will it take for your savings to increase to $12,000? 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=8000r=0.03n=1A=12000
Use formula and solve: Use the formula A=P(1+nr)nt and solve for t. 12000=8000(1+10.03)1⋅t12000=8000(1.03)t
Divide to isolate: Divide both sides by 8000 to isolate (1.03)t. 800012000=(1.03)t1.5=(1.03)t
Take natural logarithm: Take the natural logarithm (ln) of both sides to solve for t. ln(1.5)=ln((1.03)t)ln(1.5)=t⋅ln(1.03)
Divide to isolate: Divide both sides by ln(1.03) to isolate t. t=ln(1.03)ln(1.5)t≈0.0295590.405465t≈13.72
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