A data set of the ages of a sample of 425 Galapagos tortoises has a minimum value of 1 years and a maximum value of 105 years. Suppose we want to group these data into five classes of equal width.
Assuming we take the lower limit of the first class as 1 year, determine the class limits, boundaries, and
midpoints for a grouped quantitative data table.
Hint: To determine the class width, subtract the minimum age (1) from the maximum age (105), divide by
the number of classes (5), and round the solution to the next highest whole number.
Class width =
Class Limits
Lower Boundary Upper Boundary Class Midpoint
to
0.5
to
to
to
to
105.5