`r = 7%` Find the time necessary for $1000 to double when it is invested at a rate of r compounded (a) anually, (b) monthly, (c) daily, and (d) continuously

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Formula for compounding n times per year `A=P(1+r/n)^(nt)`

Formula for compounding continuously `A=Pe^(rt)`

A=Final Amount

P=Initial Amount

r=rate of investment expressed as a decimal

n=number of compoundings per year

t= time in years


a) r=7%  n=1 (annually)







Final answer: 10.24 years


b) r=7% n=12 (monthly)







Final Answer: 9.93 years


c) r=7%  t=365 (daily)







Final answer: 9.90 years


d) r=7% compounded continously







Final answer: 9.90 years