approximation

Interest Rate Approximations: Approximates a yield rate of interest based on 4 methods:
1) Max Yield denoted as i_max
2) Min Yield denoted as i_min
3) Constant Ratio denoted as i_cr
4) Direct Ratio denoted as i_dr

Calculates the probability of 3 separate events that follow a binomial distribution. It calculates the probability of exactly k successes, no more than k successes, and greater than k successes as well as the mean, variance, standard deviation, skewness and kurtosis.
Also calculates the normal approximation to the binomial distribution with and without the continuity correction factor
Calculates moment number t using the moment generating function

Calculates the yield rate of bonds using the Yield Approximation Method or the Bond Salesman Method.

Calculates the following factorial items:
* A factorial of one number such as n!
* A factorial of a numerator divided by a factorial of a denominator such as n!m!/a!b!
* Double Factorials such as n!!
* Stirlings Approximation for n!

Calculates how long it would take money to double (doubling time) using the rule of 72 interest approximation as well as showing the mathematical proof of the Rule of 72.