1. Invitations were sent to 10 relatives for a family get-together. Only 2 relatives came. How many relatives did not come?   2. Brian weighs 18 kg. His mother is 63 kg. How much more is his mother's weight (in kg)?   3. Mr. Smith will be 38 next year. His son is 26 years younger than him. How many years old is his son at present?   4. A family party has 27 adults, 7 boys, and 8 girls. How many more adults are there at the party than children?   5. Graham is 13 years old. His aunt is 38. How many years older than him is his aunt?