The two types of ogives are less than ogive and greater than or more than ogive. In a less than ogive, the frequencies of all preceding classes are added to the frequency of a class. In a more than ogive, the frequencies of the succeeding classes are added to the frequency of a class.

According to the ‘Less than’ and ‘More than’ Ogive Approach, to determine the median of a given series, both less than and more than, ogives are presented on a graph simultaneously. The perpendicular on the X-axis drawn from the point at which both the ogive curves cut each other, is the median value of the given series.

The less than ogive curve gives cumulative frequency (probability) for x <=a. The more than ogive curve gives cumulative frequency (probability) for x >=a. They intersect exactly at the median, as cumulative frequency will be % of the total at median. The 'less than' ogive curve and the 'more than' ogive curve intersect at Median.