Calculate the Population Standard Deviation. 1  Calculate the mean or average of each data set. 2  Add up all the numbers in a data set and divide by the total number of pieces of data. 3  For example, if you have found numbers in a data set, divide the sum by 4.4  This is the mean of the data set.alculate the Population Standard Deviation. 1  Calculate the mean or average of each data set. 2  Add up all the numbers in a data set and divide by the total number of pieces of data. 3  For example, if you have found numbers in a data set, divide the sum by 4.
It takes about three days to four days for your milk to come in, if youâre a first-time mum. If you've had a baby before, it can happen earlier than this. Your breasts will start to feel full a couple of days after giving birth, which is a sign that your milk is coming in.
Holstein cows typically calve for the first time when they are 23 to 26 months of age, with healthy calves weighing an average of 80 to 100 pounds at birth. Holsteins have a gestation period of nine months. Holstein cows give more milk than any other dairy breed in the U.S. The average Holstein cow produces around 23,000 pounds of milk, or 2,674 gallons, of milk each lactation. With a standard lactation lasting 305 days, that comes out to 75 pounds, or almost 9 gallons of milk per cow per day.