The ___ of a class interval is called its class mark.
Lower limit
Upper limit
Width
Mid - point
The mid - point of class interval is called its class mark.
Class mark of a certain class interval is 30 and its lower class limit is 20. Then its upper class limit is
Under Exclusive method,
(a) the upper class limit of a class is excluded in the class interval
(b) the upper class limit of a class is included in the class interval
(c) the lower class limit of a class is excluded in the class interval
(d) the lower class limit of a class is included in the class interval