How to Solve Probability in Excel

Solving probability in Excel is done using one of the functions featured in Excel. Probability can be done different ways with different functions. The most common type of statistical probability is called the Normal Probability Distribution, Normal Bell Curve, or Gaussian Distribution. Excel performs this calculation with the NORMDIST function, which is short for Normal Distribution. A Normal Probability Distribution is a form of probability with data that goes from low to high and back down to low on a bell curve. This shows that data clusters around a mean, which is the average of all of the data, with an average deviation above and below the mean. It can be used to determine various probabilities based on a data input using the mean and standard deviation. An example follows each step in parentheses.

Things You'll Need

• Microsoft Office Excel

Instructions

1. Define your data and determine what information is sought. (Nationwide SAT scores are distributed with a mean of 500 and standard deviation of 100. What is the probability of a student scoring less than 600 points?)

2. Open a new worksheet in Microsoft Excel Highlight cell A1. It can be any cell. This is where the function solution will be sent.

3. Go up to "Insert" menu and choose "Function" to open the "Insert Function" window. Select the category "Statistical" from the dropdown menu and choose "NORMDIST" in the bottom menu. Click "OK." There are dozens of other available functions, each for a different statistic.

4. Enter the data into the NORMDIST Function Arguments window. The answer will show up on this window and in cell A1 when you click "OK". (Our example's question has a given value of 600, which is our x. The other information is given in the given data. Mean is 500 and Standard deviation is 100. Cumulative is set to "TRUE." The answer is 0.84134474, so the probability that a student's score is below 600 points is about 84.1%.)

Resources

• Read this Article in Spanish
• Business Statistics