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Calcrivo

Normal Distribution Calculator

Compute PDF, CDF, and inverse CDF for the normal (Gaussian) distribution with given μ and σ.

Inputs

P(X ≤ x)

0.97500217

PDF f(x)

0.05844094

P(X > x)

0.02499783

Mean

0.0000

Variance

1.0000

Step by step

  1. Values used

    Mean (μ) = 0; Standard Deviation (σ) = 1; x value = 1.96

  2. PDF

    f(x) = (1/(σ√(2π))) × exp(−(x−μ)²/(2σ²))

  3. Standard Z

    z = (x − μ) / σ

  4. P(X ≤ x)

    = 0.97500217

  5. PDF f(x)

    = 0.05844094

  6. P(X > x)

    = 0.02499783

  7. Mean

    = 0.0000

  8. Variance

    = 1.0000

How it works

The normal (Gaussian) distribution is the most important continuous distribution in statistics. It is completely defined by its mean μ and standard deviation σ. About 68% of values lie within 1σ of the mean, 95% within 2σ, and 99.7% within 3σ.

Formulas

PDF

f(x) = (1/(σ√(2π))) × exp(−(x−μ)²/(2σ²))

μ
Mean
σ
Standard deviation
x
Point of evaluation

Standard Z

z = (x − μ) / σ

x
Value
μ
Mean
σ
Standard deviation

Frequently Asked Questions

What is the standard normal distribution?

It is the normal distribution with μ = 0 and σ = 1. Any normal variable can be converted to standard normal using z = (x − μ)/σ.

Why is the normal distribution so important?

The Central Limit Theorem states that the sum (or mean) of many independent random variables tends toward a normal distribution regardless of the underlying distribution.

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