Plany

Kalkulator średniej ważonej

Ten kalkulator oblicza średnią, gdy niektóre wartości liczą się bardziej niż inne, np. oceny o różnych wagach. Wpisz wartości i ich wagi; kalkulator mnoży, dodaje i dzieli, pokazując każdy krok.

Oddziel wartości przecinkami lub spacjami.
Wagi mogą być procentami, punktami ECTS lub liczebnościami.

Wynik

Wpisz wartości i naciśnij Oblicz, aby zobaczyć wynik.

Wzór

xˉw=∑wixi∑wi\bar{x}_w = \frac{\sum w_i x_i}{\sum w_i}

Multiply each value by its weight, add the results, then divide by the total weight.

Jak korzystać z tego kalkulatora

  1. Enter the values, then their weights in the same order.
  2. Weights do not need to add up to 1 or 100: the calculator divides by their total.
  3. Press Calculate to see the weighted average and the working.

Rozwiązane przykłady

Marks 80, 90 and 70 with weights 2, 3 and 5

80 × 2 + 90 × 3 + 70 × 5 = 160 + 270 + 350 = 780.

The weights add up to 10, so the weighted average is 780 ÷ 10 = 78.

Percent weights: 72 (40%) and 85 (60%)

72 × 40 + 85 × 60 = 2880 + 5100 = 7980.

7980 ÷ 100 = 79.8.

Częste błędy

  • Taking the ordinary mean, which treats every value as equally important.
  • Dividing by the number of values instead of the total weight.
  • Listing weights in a different order from the values.

Najczęstsze pytania

How do you calculate a weighted average?

Multiply each value by its weight, add these products, and divide by the sum of the weights.

Do the weights have to add up to 100%?

No. Dividing by the total weight takes care of it: weights 2, 3, 5 work the same as 20%, 30%, 50%.

When is a weighted average used?

Course grades with weighted assignments, grade point averages with credit hours, and averaging prices bought in different quantities.