Please Help I don’t understand

Which phrase generalizes the specific terminology bolded in the text?

Oliver makes blueberry jam every year. the number of kinds of jam he makes this year can be represented by the expression 4p -9, where p is the number of pints he made last year

On the blueprint of a house, 42 millimeters represents 8 meters. the actual lehenth of the living room is 5 meters. what is the length on the blueprint