posted by kelly .
how do you find the lower class limit,upper class limit, class width, class midpoint, and class boundaries from a set of frequencies data
Sort out the data in increasing order.
If there are n pieces of data, calculate nc=√n to be the number of classes. Round up to the next integer if necessary.
Find class width by dividing n by nc. Again round up to the next integer if necessary.
Start the first class with the smallest value (or smallest value -1) and increment each class start point by adding class width to the previous.