Echocardiogram - Echo. 1  Problems with the outer lining of your heart (the pericardium). 2  Problems with the large blood vessels that enter and leave the heart. 3  Blood clots in the chambers of your heart. 4  Abnormal holes between the chambers of the heart.
(3) Select the smallest observed value as the lower limit of the first class (e.g. the left hand value for the first class), and add multiples of the class width from step (2) to obtain the lower limits for each class. So in the black bear case, the lower class limits would be. 16.0, 26.2, 36.4, 46.6, , 107.8. (4) Find the upper class limits (the right hand value for each class) by adding the class width to the lower class limits and subtracting from this the smallest significant digit in the observations.
To obtain the other upper class limits, you repeatedly add the class width to the first upper class limit until-including the first upper class limit-you have one upper class limit for each class. 8. For each class, count the number of data values in the class. This is the class frequency. You can do this by going through the data values one by one and making a tally mark next to the class where the data value occurs. Counting up the tallies for each class gives the class frequency. The class frequencies should be recorded in their own column.