Adam Hayes, Ph.D., CFA, is a financial writer with 15+ years Wall Street experience as a derivatives trader. Besides his extensive derivative trading expertise, Adam is an expert in economics and ...

Calculating the mean is one of many methods of finding an average. To calculate the mean, you add up all the numbers in the set, then divide the total by the number of numbers you added.

Image caption, To find the mean age, use a calculator to divide the total age of all the children (168) by how many children there are (15). 168 ÷ 15 = 11.2. The mean age is 11.2 years old.

Against that backdrop, parents may have questions about what this initiative will mean for what’s on store ... has written extensively about infant formula. “The answer is, it’s always ...