Financial Math

Like any rule of thumb, this rule is only good for approximations. Next give a derivation of the exact number for the case of an interest rate of 10%. How long does it take a given principal, P, to double given either the interest rate r (in percent per year) or the number of years n? Solving this equation: P(1 + r/100)n = 2P . Try the case of ... ................
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