Change

⁂ To know how many changes can be rung on a peal of bells, multiply the known preceding number by the next subsequent one, thus: 1 bell no change; 2 bells, 1 X 2 = 2 changes; 3 bells, 2 X 3 = 6 changes; 4 bells, 6 X 4 = 24 changes; 5 bells, 24 X 5 = 120 changes; 6 bells, 720 changes, etc.

Take your change out of that. Said to a person who insults you when you give him a quid pro quo, and tell him to take out the change. It is an allusion to shopping transactions, where you settle the price of the article, and put the surplus or change in your pocket.