If the interest earned by a CD is compounded annually

Question

If the interest earned by a CD is compounded annually, which rule is most accurate when calculating how long it will take the money invested in the CD to double?

Answer 1

Compound interest:  A = p(1+r/n)^nt

A = future amount = 2p

p = principle investment

r = interest rate as a decimal

n = # times compounded yearly = 1

t = time in years

 

2p = p(1+r/1)^1(t)

 

2 = (1+r)^t