How is weighted average calculated?

Weighted avg = Σ(value × weight) / Σ(weight).

Online Weighted Average Calculator

Calculate weighted average. Enter values and their weights (e.g. grades and credits).

Value, weight (one per line, e.g. 90 3)

How is weighted average calculated?: Weighted avg = Σ(value × weight) / Σ(weight).

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Calculate C(n,r) — the number of ways to choose r items from n without order. Uses n!/(r!(n-r)!).

Combinations with Replacement Calculator

Calculate the number of ways to choose r items from n with repetition allowed. Formula: C(n+r-1, r).

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Count how many permutations of n objects are even (expressible as an even number of swaps). For n ≥ 2, equals n!/2.