Aptitude Topics
Weighted Average
Calculates an average value where certain data components have higher contextual value than others.
Fundamental Principles
Weighted Mean
The sum of the product of weights and corresponding values, divided by the sum of total weights.
Essential Formulation Tips
- Identify clearly what represents the values and what constitutes the weights.
- Weights can be quantities, percentages, ratios, or frequencies.
Shortcut Execution Techniques
- You can simplify weights by reducing them to their simplest ratio form to calculate answers faster.
Contextual Inquiries (FAQs)
Q: When do we use weighted average?
A: When combining items of varying importance, like semester grades with different course credit hours.
Example Breakdown: Combining Two Classes
Classic composite group problem.Problem QueryClass A has 20 students averaging 60 marks. Class B has 30 students averaging 70 marks. Find the combined average.
Step-By-Step Solution Path
Total marks = (20 * 60) + (30 * 70) = 1200 + 2100 = 3300
Total students = 20 + 30 = 50
Weighted Average = 3300 / 50 = 66
Analytical Hint: Find the total collective sum first.
Weighted Average Practice Set 1
Questions focused on combined groups and credit parameters.
Q1. Buy 2 kg sugar at $30/kg and 3 kg sugar at $40/kg. What is the average price per kg?