Question

Five years ago, John’s age was half of the age of Mary. John is 4 years younger than Mary now. How old is John now?

Answer 1

Answer:

Five years ago John was (still; as always) 4 years younger than Mary and he was half of her age ====> hence, his age then was 4 years, while Mary's age was 8 years at that time. It means that now John is 4 + 5 = 9 years old, while Mary is 8 + 5 = 13 years old.