The amount of money in an account with continuously compounded interest is given by the formula A = Pert , where P is the princi
pal, r is the annual interest rate, and t is the time in years. Calculate to the nearest hundredth of a year how long it takes for an amount of money to double if interest is compounded continuously at 3.1%. Round to the nearest tenth.
A=future amount P=present amount r=rate in decimal t=time in years
when A=2P, then that is double A=Pe^(rt) 2P=Pe^(rt) divide by P 2=e^(rt) r=3.1% or 0.031 solve for t 2=e^(0.031t) take the ln of both sides ln(2)=0.031t divide both sides by 0.031 (ln(2))/0.031=t use calculator 22.359=t round to tenth 22.4 years to double
