Calculate the Sample Standard Deviation. 1  Calculate the mean or average of each data set. 2  To do this, 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.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.
Most pregnant women begin to show during the second trimester. You likely gained less than 5 pounds during your first trimester, but now the number on the scale is edging relentlessly upward. As your second trimester proceeds, you'll gain an average of 1 to 2 pounds per week.
Approximately four days after fertilization, the egg will start to produce a pregnancy hormone called human chorionic gonadotropin (hGC). A pregnancy test will detect this hormone about one week after fertilization. Most women tend to wait to take a pregnancy test until after they have missed one menstrual period. If you take a pregnancy test one week after you were supposed to get your period, the result will be about 95% accurate. If you take it too soon after fertilization, it may show up negative when in fact you really are pregnant. Pregnancy test are meant to be considered screening tests.