Formulas
How to Use
Type or paste your numbers separated by commas, spaces, or new lines.
Hit Calculate to get the average along with sum, count, min, max and range.
Use the Weighted Average tab when each value has a different importance or weight.
Frequently Asked Questions
Average = Sum of all values ÷ Number of values. For example, average of 10, 20, 30 = (10+20+30) ÷ 3 = 20.
Old sum = 5 × 20 = 100. New sum = 6 × 25 = 150. 6th number = 150 − 100 = 50.
A weighted average gives different importance (weight) to different values. Formula: WA = Σ(value × weight) ÷ Σ(weight). Example: a student scores 80 in a 3-credit subject and 60 in a 2-credit subject → WA = (80×3 + 60×2) / (3+2) = 360/5 = 72. Used in mixture, alligation, and marks calculation problems.
These three results are used repeatedly in SSC and IBPS exams: First n natural numbers: average = (n+1)/2. First n even numbers (2,4,...,2n): average = n+1. First n odd numbers (1,3,...,2n−1): average = n. Example: average of first 10 natural numbers = 11/2 = 5.5; first 10 even numbers = 11; first 10 odd numbers = 10.
Total score = 11 × 40 = 440. Score of remaining 10 = 10 × 38 = 380. Captain's score = 440 − 380 = 60. Shortcut: captain's score = new average + n × (old avg − new avg) = 38 + 10 × 2 = 58... more precisely = (11 × 40) − (10 × 38) = 60. This "removing one value" pattern appears very frequently in competitive exams.