Short Cut Math ```Name: Loretta S Status: N/A Age: N/A Location: N/A Country: N/A Date: N/A ``` Question: For compound interest that equation is T=P(1+r)to the n power my question is...What is a short cut to find the answer for n besides guess and check? Replies: ln(x^n) = n ln(x) Tim Mooney Dear Loretta, Algebra and logs are the keys to solving for n. Given: T = P(1+r)^n Solve for n 1.Divide both sides by P T/P = (1+r)^n 2.Take the log of both sides (any log will do, I like the natural log) ln (T/P) = ln [(1+r)^n] 3.When you take a log, one property is that any exponents of inside the log become coefficients of the log itself. ln (T/P) = n [ln (1+r)] 4.Divide both sides by [ln (1+r)]. [ln(T/P)]/[ln (1+r)] = n This will give you a definitive answer for n, without guessing and checking. Click here to return to the Mathematics Archives

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