Q. Rachel deposited 10$ in an account earning 5% interest compounded annually. To the nearest cent, how much interest will she earn in 3 years? $____
Identify values: Identify the principal amount, interest rate, and time period.Rachel deposited $10 at an interest rate of 5% per annum, compounded annually, for a period of 3 years.Principal (P) = $10Interest rate (r) = 5% or 0.05 (as a decimal)Time (t) = 3 years
Use compound interest formula: Use the formula for compound interest to find the total amount after 3 years.The formula for compound interest is A=P(1+r/n)(nt), where A is the amount of money accumulated after n years, including interest, P is the principal amount, r is the annual interest rate (decimal), n is the number of times that interest is compounded per year, and t is the time the money is invested for in years.Since the interest is compounded annually, n=1.A=P(1+r/n)(nt)
Substitute values into formula: Substitute the values into the formula.A=10(1+0.05/1)(1∗3)A=10(1+0.05)3A=10(1.05)3
Calculate total amount: Calculate the total amount after 3 years.A=10(1.05)3A=10(1.157625)A=11.57625
Calculate interest earned: Calculate the interest earned by subtracting the principal from the total amount.Interest earned = A−PInterest earned = 11.57625−10Interest earned = 1.57625
Round to nearest cent: Round the interest earned to the nearest cent.Interest earned = $1.58 (rounded to the nearest cent)
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