Statistics: A branch of mathematics dealing with the collection, analysis, interpretation, and presentation of masses of numerical data.
Data: Collection of meaningful informations.
Two types of Data: Ungrouped data and Grouped data
Measure of Central Tendency: It means a center or location of the distribution. The most common measures of central tendency are the arithmetic mean, the median, and the mode
Empirical relationship between three measures of central tendency: Mode = 3 Median – 2 mean
Median class: A class where the cumulative frequency reaches half the sum of the absolute frequencies.
Modal Class: A class interval having maximum frequency.