Averages — Sum ÷ Count, Made Simple
What an average really is, the one formula, and the 'work with the total' trick for tricky problems.
By the PadhoDost Team · 📖 5 min read · Updated 4 August 2026
Part of SSC CGL & Banking prep🧠 Sharing equally
An average is what each person would get if everything were shared out equally. Three friends have ₹10, ₹20 and ₹30 — together ₹60. Shared equally that's ₹20 each. That's the average.
The only formula you need
Average = (Sum of values) ÷ (Number of values)
💡 Flip it: Sum = Average × Count. Most 'tricky' average questions are just switching between these two forms.
📝 Average age of 5 students is 12. Adding the teacher makes it 15. Teacher's age?
Students' total = 12 × 5 = 60
With teacher (6 people), total = 15 × 6 = 90
Teacher's age = 90 − 60 = 30 years
Remember
- ✓The average always lies between the smallest and largest value
- ✓Average of consecutive numbers = (first + last) ÷ 2
- ✓For changes, work with the TOTAL, not the individual values
⚡ Quick check
The average of 5 numbers is 20. What is their sum?
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