# Time to Double or Triple an Investment

### Time to Double/Triple Investment Formula

A = Pe^

^{rt}

### Sample Problem

If r = 5%, then to find double time, the formula looks like the following;

2P = Pe^

we then divide both sides by P, so the equation is now;

2 = e^

multiply both sides by ln

.05t = ln2

divide by .05

t = ln2 / .05

t = 13.86 years

therefore, it will take 13.86 years to double your investment based on an interest rate of 5%

2P = Pe^

^{.05t}we then divide both sides by P, so the equation is now;

2 = e^

^{.05t}multiply both sides by ln

.05t = ln2

divide by .05

t = ln2 / .05

t = 13.86 years

therefore, it will take 13.86 years to double your investment based on an interest rate of 5%