You invested $5,000 in a savings account, and after 10 years, the balance grew to $8,144. The interest is compounded annually. What is the annual interest rate? 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 tenth.
Q. You invested $5,000 in a savings account, and after 10 years, the balance grew to $8,144. The interest is compounded annually. What is the annual interest rate? 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 tenth.
Identify values: Identify the values of A, P, n, and t. A=$8,144P=$5,000n=1 (compounded annually) t=10 years
Substitute values: Substitute the values into the formula A=P(1+nr)nt. 8,144=5,000(1+1r)1⋅10
Simplify equation: Simplify the equation. 8,144=5,000(1+r)10
Divide sides: Divide both sides by 5,000 to isolate (1+r)10. (1+r)10=5,0008,144(1+r)10=1.6288
Take 10th root: Take the 10th root of both sides to solve for (1+r). 1+r=(1.6288)(1/10)1+r≈1.0500
Subtract to solve: Subtract 1 from both sides to solve for r. r≈1.0500−1r≈0.0500
Convert to percentage: Convert r to a percentage. r≈0.0500×100% r≈5.0%
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