Five years ago, the average age of A and B was 15 years. The average age of A, B, and C today is 20 years. How old will C be in 10 years?
Q1. Five years ago, the average age of A and B was 15 years. The average age of A, B, and C today is 20 years. How old will C be in 10 years?
Answer: 30 years
Explanation: Five years ago A+B averaged 15, so current A+B = 40; today A+B+C = 60; C = 20, and in 10 years C will be 30.