## How do you calculate doubling time of money?

“The Rule of 72 is a rule of thumb that helps one find the approximate time it takes to double one’s investment given the rate of return. For example, at 9% p.a., it should take 72/9 = 8 years (approximately) to double the money.

**How long does it take to invest 9% to double?**

eight years

For example, with a 9% rate of return, the simple calculation returns a time to double of eight years.

### How many years will it take for an investment to double if the interest rate is 8% per year compounded annually?

approximately nine years

For example, if an investment scheme promises an 8% annual compounded rate of return, it will take approximately nine years (72 / 8 = 9) to double the invested money.

**What is the rule for doubling your money?**

The Rule of 72 is a calculation that estimates the number of years it takes to double your money at a specified rate of return. If, for example, your account earns 4 percent, divide 72 by 4 to get the number of years it will take for your money to double.

## Why do we use 72 in the Rule of 72?

The actual number of years comes from a logarithmic calculation, one you can’t really determine without having a calculator with logarithmic capabilities. That’s why the rule of 72 exists; it lets you basically figure out how long it will take to double without requiring an actual physical calculator on your person.

**Why does the 72 rule work?**

The Rule of 72 is a simple way to determine how long an investment will take to double given a fixed annual rate of interest. By dividing 72 by the annual rate of return, investors obtain a rough estimate of how many years it will take for the initial investment to duplicate itself.

### How long will it take for $7000 to double at the rate of 8 %?

9 years

The rule says that to find the number of years required to double your money at a given interest rate, you just divide the interest rate into 72. For example, if you want to know how long it will take to double your money at eight percent interest, divide 8 into 72 and get 9 years.

**How long will it take for $7000 to double at the rate of 8 %? *?**

## How long does it take to double your money at 5 percent interest?

about 14.4 years

According to the Rule of 72, it would take about 14.4 years to double your money at 5% per year.

**How long does it take to double your money at 8 percent?**

about 9 years

The principle is simple. Divide 72 by the annual rate of return to figure how long it will take to double your money. For example, if you earn an 8 percent annual return, it will take about 9 years to double.

### Did Albert Einstein invent the Rule of 72?

The Rule of 72 was discovered by Albert Einstein and he considered it his greatest discovery even over E=MC2 (Squared). He considered it the most powerful force on earth. In its simplest form Einstein explained it this way. When you invest money, you earn interest on your capital.

**Why do banks use 360 days instead of 365 method?**

Because the yearly rate is divided by 360, the daily rate is greater than the rate obtained by dividing it by 365, resulting in a higher dollar amount of interest payments.