... James has a times as many as John, and Charles hasd less than five times as many as James. How many has Charles?30. A man bought a pounds of meat at a cents a pound, and handed the butcher an ... − 3a, − 2a, a, −0, a, 2a, 3a, 4a, 5a. What must be added to 2a to obtain 5a? What then must be subtractedfrom 5a to obtain 2a? 5a − 3a =?What must be added to − 3a to obtain 4a? What then must ... of arithmetic;abundant practice is given in the representation of numbers by letters, and greatcare is taken to make clear the meaning of the minus sign as applied to a singlenumber, together...