Average (Mean)
Average = (a + b + c) ÷ 3
Calculate the average of three numbers
Median Calculator
Middle value of ordered data set
Find the median (middle value) of a set of numbers
Mode Calculator
Most frequently occurring value
Find the mode (most common value) in a set of numbers
Standard Deviation
σ = √(Σ(x - μ)² ÷ n)
Calculate standard deviation of a data set
Variance Calculator
σ² = Σ(x - μ)² ÷ n
Calculate the variance of a data set
Factorial Calculator
n! = n × (n-1) × ... × 2 × 1
Calculate the factorial of a number
Partner Spotlight
Combinations (nCr)
nCr = n! / (r! × (n - r)!)
Count how many ways r items can be chosen from n when order does not matter
Permutations (nPr)
nPr = n! / (n - r)!
Count how many ways r items can be arranged from n when order matters
Z-Score Calculator
z = (x - μ) / σ
Find how many standard deviations a value is from the mean
Probability Calculator
P(A) = Number of favorable outcomes ÷ Total outcomes
Calculate probability of an event
Binomial Probability
P(X = k) = nCk × pᵏ × (1-p)⁽ⁿ⁻ᵏ⁾
Probability of exactly k successes in n independent trials
Normal Distribution
f(x) = (1/σ√(2π)) × e^(-½((x-μ)/σ)²)
Calculate probability density for normal distribution
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Range Calculator
Range = maximum - minimum
Find the range of a data set
Weighted Average
Weighted Average = (v₁w₁ + v₂w₂) / (w₁ + w₂)
Calculate the weighted average of two values
Confidence Interval (Margin of Error)
ME = z × (σ / √n)
Calculate the margin of error and confidence interval for a sample mean
