Question: Rearrange formulae View Single Post
 ebaines Posts: 10,138, Reputation: 5589 Expert #4 Jan 31, 2012, 07:54 AM
$
M = P(1+IR) + (P(1+IR))^n
$

If you replace P(1+IR) with a, you have:

$
M = a + a^n
$

Unfortunately there is no closed form solution to express a in terms of M and n. If n = 2 you can use the quadratic equation to solve for a. But other than that case - you're limited to using numerical techniques to estimate a. Once you have that estimate then IR=(a/P)-1