Weighted Average — Prelims Questions

A class has 25 students with an average score of 78 in Mathematics, and 35 students with an average score of 84 in the same subject. If these two groups are combined, what is the overall average score?

A solution contains 40% acid. If 60 liters of this solution is mixed with 40 liters of another solution containing 25% acid, what is the concentration of acid in the final mixture?

In a company, the average salary of 20 managers is ₹80,000 and the average salary of 30 executives is ₹60,000. What is the average salary of all employees combined?

A student scores 85 in Subject A (3 credits), 90 in Subject B (4 credits), and 75 in Subject C (2 credits). What is the weighted average score based on credit hours?

Two alloys contain copper in the ratio 3:2 and 2:3 respectively. If equal weights of both alloys are melted together, what is the ratio of copper in the new alloy?