It is the study of the collection, organizing, analysis and presentation of the data.
Mean (µ) is the average of all the terms. Add up all the terms and then divide it by the number of terms. It is also called as arithmetic mean or average.
Place the values in ascending or descending order.
If number of terms is odd, then middle term = (n+1)⁄2 is the median.
If number of terms is even, then median is the average of middle terms n⁄2 and n⁄2 + 1.
Mode is the value that occurs most often in the set of values.
It is the difference between maximum and minimum values.
Example 1: What is the mode of 12, 45, 37, 23, 12, 27, 4, 42, 23, 45, 12?
(a) 23 (b) 45 (c) 12 (d) 27
12 is repeated three times.
23 is repeated two times.
45 is repeated two times.
Hence 12 is the answer.
Example 2: Find the mean, median and mode for 3, 4, 8, 9
Mean = (3+4+8+9)/4 = 24/4 = 6
Median = (4+8)/2 = 12/2 = 6
There is no mode.