A is older than B by 5 years. If the sum of their ages is 25, how old is A?
Q1. A is older than B by 5 years. If the sum of their ages is 25, how old is A?
Answer: 15
Explanation: Let's denote A's age as x and B's age as y. So, x = y + 5 and x + y = 25. Substituting x in the second equation gives y + 5 + y = 25, simplifying to 2y = 20, hence y = 10, and x = 15.