RULE 72

RULE 72, can be used to estimate approximate time required to double any investement at a given interest rate compounded annually. According to the rule just divide 72 by the interset rate and the result is the approximate time required to double the invested amount.

For instance, if you invest Rs.1000 with compounding interest at a rate of 8% per annum,
According to RULE 72 it would take around 9 years (72/9 = 9 years) for the invested amount to become Rs. 2000

More read: http://en.wikipedia.org/wiki/Rule_of_72

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