What is the side lenth of the largest and the smallest square that could be used to tile a rectangle that is 8in by 36in? (can anyone explain in detail? i never really fully understood the way i was taught this)

Players on the school soccer team are selling candles to raise money for an upcoming trip. each player has 24 candles to sell. if a player sells 4 candles a profit of$30 is made. if he sells 12 candles a profit of $70 is made. determine an equation to model his situation?