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.
1 He should be able to hold his head up and sit in a feeding chair or infant seat.  Weaning from breast milk: Your baby needs nutrients from breast milk until he is at least 12 months old. If you choose to stop breastfeeding your baby before he is 12 months old, you will need to bottle-feed him formula. His body needs the nutrients that breast milk and formula provide until he is 12 months old.