and therefore how much it will cost. At a petrol station the customer puts as much petrol as they want into their vehicle and the merchant has to calculate what quantity that is and then calculate the price. The customer specifies the particular piece of land they want to purchase, and the seller has to calculate the area of that piece of land in order to determine the sale price.

The system of sale where the seller has to calculate the quantity has been known as haberdashery since at least as early as 1533 when an act of the English