Retail analog scales provide a measurement of products that are sold by weight. To know how much you must pay for an item sold by the pound, for example, you need to know how many pounds or fractions of a pound you are getting ready to buy. Placing the item on a scale gives you a weight reading. You'll typically find these types of scales in a grocery store's produce section. Retail stores use analog scales because they are less expensive (and less accurate) than digital scales.
Make sure the scale is properly calibrated by placing an item with a known weight on the scale and comparing it to the reading. For example, a 1-pound weight should register precisely 1 pound when placed on the analog scale.
If you don't have a test weight and want to check a scale's accuracy in a grocery store, grab an item off the shelf, such as a small, 2-pound bag of sugar, and place the item on the scale.
Read the information on the dial of the scale. In the United States, analog scales are marked in pound measurements. Each pound is represented by a numeral: 1, 2, 3, and so on. When weight is placed upon the scale, a red needle turns clockwise to point at the weight number.
Understand the individual gradations between numbers. Analog scales are made up of a series of hash marks between the numbers, which represent whole pounds. Each hash mark represents a fraction of a pound. The large hash mark between numbers is the 1/2-pound mark, and the smaller marks on either side represent 1/4 and 3/4 pound. The marks between the 1/4 and 3/4 marks represent 1/8 of a pound. You can count the marks to add up fractions of a pound until you learn to recognize the different lengths of the marks and adding them up in your head becomes second nature.
Read a retail analog scale to determine weight, then calculate the price of the weighed merchandise. For example, if you place a scoop of roasted macadamia nuts on an analog scale and the needle stops at the middle hash mark between the 1 and the 2, you have 1 1/2 pounds of macadamias on the scale. If the need stops at the smaller mark beyond the 1/2-pound mark, then you have 1 3/4 pounds of macadamias.
Calculate the price by multiplying the number of pounds by the price per pound. If macadamia nuts cost $12 per pound and you have weighed 1 1/2 pounds of nuts, then the total price would be 12 x 1.5, which is $18.