1. Invitations were sent to 25 relatives for a family get-together. Only 23 relatives came. How many relatives did not come?   2. Gary weighs 20 kg. His mother is 58 kg. How much more is his mother's weight (in kg)?   3. Mr. Brown will be 38 next year. His son is 27 years younger than him. How many years old is his son at present?   4. A family party has 54 adults, 16 boys, and 16 girls. How many more adults are there at the party than children?   5. Warren is 13 years old. His aunt is 40. How many years older than him is his aunt?