# Rule of 72

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## Rule of 72

A formula used to determine the amount of time it will take for invested money to double at a given compound interest rate, which is 72 divided by the interest rate. The logic is as follows. The time for an amount A to double is given by 2A=A(1+i)^t where ^ represents exponent and i is the interest rate, e.g. .05 is 5%. The A term cancels from both sides of the question. Solve for t by taking the natural log of both sides of the equation. Hence, t= [ln(2) over {ln(1+i)}], which is approximately equal to 0.72 over i. Hence the rule of 72.

## Rule of 72

A rule of thumb estimating how long it will take for an investment to double. One calculates this by dividing 72 by the rate of return. The rule of 72 is not exact, but it provides a quick look at the effects of compounding on an investment.

## rule of 72

The mathematical rule used in approximating the number of years it will take a given investment to double in value. The number of years to double an investment is calculated by dividing 72 by the annual rate of return. Thus, an investment expected to earn 10% annually will double the investor's funds in 72/10 , or 7.2 years. Dividing 72 by the number of years in which the investor wishes to double his or her funds will yield the necessary rate of return.
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RULE OF 72 Rule of 72 refers to the time value of money.
In the new series, Kathryn deals with a family where the kids are running riot because the mum's lost her confidence and the dad's more concerned with checking his smartphone; a single nursery school teacher mum who's imposed such a strict regime on her kids that Kathryn counts 72 rules in just her first few hours in the house; and a family where the three-year-old daughter rules the household.
There's a nursery school teacher and single mum who's imposed such a strict regime on her kids that Kathryn counts 72 rules within hours of arriving.
This will be a surprise to GPs who via Section 72 rules are being forced to open up every part of health services to private companies, whether or not it's what they, their patients or their community wants.
This method was applied and more than halved the number of association rules, leaving 72 rules, some of which comprised the same courses in different order.
Furthermore, inspection of the whole 72 rules led to the discovery of six additional 'clusters'.
I accept that my method of 'clustering' the data was somewhat arbitrary and that if another analyst were to cluster the 72 rules given in Table 10, for example, then a different set of groupings may well emerge.
72 rules for income taxation of distributions from an annuity.
For example, the Code of Professional Ethics of Rehabilitation Counselors consists of 10 canons and 72 rules, one of which specifically references the rehabilitation counselor as a supervisor.

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