| flour || style="color:green;"| 100% ||style="color:maroon;"| 56.88% |- | align=left | water || 35% ||style="color:maroon;"| 19.91% |- | align=left | milk || 35% ||style="color:maroon;"| 19.91% |- | align=left | fresh yeast || 4% ||style="color:maroon;"| 2.28% |- | align=left | salt || 1.8% ||style="color:maroon;"| 1.02% |- ! align=right | Total ||style="color:red;"| 175.8% ||style="color:green;"| 100% |} The total or sum of the baker's percentages is called the formula percentage. The sum of the ingredient masses is called the formula mass (or formula "weight"). Here are some interesting calculations: The flour's mass times the formula percentage equals the formula mass: An ingredient's mass is obtained by multiplying the formula mass by that ingredient's true percentage; because an ingredient's true percentage is that ingredient's baker's percentage divided by the formula percentage expressed as parts per hundred, an ingredient's mass can also be obtained by multiplying the formula mass by the ingredient's baker's percentage and then dividing the result by the formula percentage: Thus, it is not necessary to calculate each ingredient's true percentage in order to calculate each ingredient's mass, provided the formula mass and the baker's percentages are known. Ingredients' masses can also be obtained by first calculating the mass of the flour then using baker's percentages to calculate remaining ingredient masses: The two methods of calculating the mass of an ingredient are equivalent: Weights and densities The use of customary U.S. units can sometimes be awkward and the metric system makes these conversions simpler. In the metric system, there are only a small number of basic measures of relevance to cooking: the gram (g) for weight, the liter (L) for volume, the meter (m) for length, and degrees Celsius (°C) for temperature; multiples and sub-multiples are indicated by prefixes, two commonly used metric cooking prefixes are milli- (m-) and kilo- (k-). Intra-metric conversions involve moving the decimal point. Common avoirdupois and metric weight equivalences: 1 pound (lb) = 16 ounces (oz) 1 kilogram (kg) = 1,000 grams (g) = 2.20462262 lb 1 lb = 453.59237 g = 0.45359237 kg 1 oz = 28.3495231 g. In four different English-language countries of recipe and measuring-utensil markets, approximate cup volumes range from 236.59 to 284.1 milliliters (mL). Adaptation of volumetric recipes can be made with density approximations: {|class=wikitable |- !style="background: #D8D8D8;" colspan=8|Volume to mass conversions for some common cooking ingredients |- !rowspan=2|ingredient !rowspan=2|densityg/mL !colspan=2|metric cup250 mL !colspan=2|imperial cup≈284 mL !colspan=2|U.S. customary cup≈237 mL |- !g