1. Invitations were sent to 91 relatives for a family get-together. Only 80 relatives came. How many relatives did not come?   2.  There are five members in Robert's family. Their total weight is 287 kg. His own weight is 36 kg. How many kilograms do the other four members weigh?   3. Mr. Brown will be 60 next year. His son is 27 years younger than him. How many years old is his son at present?   4. A family party has 129 adults, 26 boys, and 12 girls. How many more adults are there at the party than children?   5. For Christmas, Mr. Hick gave $136 to his two sons. He gave $97 to the elder son. How many dollars did he give the younger son?