5200 dollars is placed in an account with an annual interest rate of 5.75%. To the nearest year, how long will it take for the account value to reach 22500 dollars?Answer:
Q. 5200 dollars is placed in an account with an annual interest rate of 5.75%. To the nearest year, how long will it take for the account value to reach 22500 dollars?Answer:
Identify Interest Type: Determine the type of interest being applied.Since the problem does not specify compound or simple interest, we will assume compound interest is applied annually.
Compound Interest Formula: Identify the formula for compound interest.The formula for compound interest is A=P(1+r/n)(nt), where:A = the amount of money accumulated after n years, including interest.P = the principal amount (the initial amount of money).r = the annual interest rate (decimal).n = the number of times that interest is compounded per year.t = the time the money is invested for, in years.Since interest is compounded annually, n=1.
Convert Interest Rate: Convert the annual interest rate from a percentage to a decimal.r=5.75%=0.0575
Set Up and Solve Equation: Set up the equation with the given values and solve for t. We have P=5200, A=22500, r=0.0575, and n=1. 22500=5200(1+0.0575/1)(1⋅t)
Simplify and Solve for t: Simplify the equation and solve for t.22500=5200(1+0.0575)tDivide both sides by 5200 to isolate the exponential part of the equation.520022500=(1+0.0575)t4.32692307692≈(1.0575)t
Use Logarithms to Solve: Use logarithms to solve for t. Take the natural logarithm (ln) of both sides to get rid of the exponent. ln(4.32692307692)=ln((1.0575)t) Use the power rule of logarithms: ln(ab)=b⋅ln(a). ln(4.32692307692)=t⋅ln(1.0575)
Calculate t Value: Calculate the value of t.t=ln(1.0575)ln(4.32692307692)t≈ln(1.0575)ln(4.32692307692)t≈0.0558925531.46510313157t≈26.21
Round to Nearest Year: Round the value of t to the nearest year.Since we need to find the nearest year, we round 26.21 to 26 years.
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