standard deviation is used to measure risks involved in an investment instrument. Standard deviation provides investors a mathematical basis for decisions to be made regarding their investment in financial market. Standard Deviation is a common term used in deals involving stocks, mutual funds, ETFs and others. Standard Deviation is also known as volatility. It gives a sense of how dispersed the data in a sample is from the mean.
4*25= 100. There are 26 tables. At each of the 25 tables 4 people are sitting. Which means 100 people are sitting in complete tables of 4 people. That means that at the 26th table 3 people are sitting. 103-100= 3. Hope that helps. :)
