Mean, Median and Mode are very interesting topics. From these 2-3 days questions can be asked in the exam. These are applied to the set of data or observations. These are explained below one by one in detail.
Mean - It is like an average. It is applicable to the set of data or observations where data is added with each other and divided by the number of data.
Median - It is the middlemost value of the data set when arranged in ascending order.
Mode - It is the occurrence of data or observation in maximum time.
Mean = $$\frac{\text{Sum of data}}{\text{Number of data}}$$
Median
If N is an odd number, then median = $$\frac{(N+1)}{2} ^{th}$$ term.
If N is an even number, then median = $$\frac{(\frac{N}{2})^{th} term + (\frac{N}{2}+1)^{th} term}{2}$$.
N = Number of data or observations
Q) Find out the means of 34, 32, 32, 28, 36, 28, 30 and 26.
Sol. Means = $$\frac{34+32+32+28+36+28+30+26}{8}$$
= $$\frac{246}{8}$$
= 30.75
Q) Find out the median and mode of 25, 24, 28, 24, 26, 25 and 24.
Sol. 24, 24, 24, 25, 25, 26, 28
Median = $$\frac{(N+1)}{2} ^{th}$$ term
= $$\frac{(7+1)}{2} ^{th}$$ term
= $$\frac{8}{2} ^{th}$$ term
= $$4 ^{th}$$ term
= 25
Here the mode is 24 which is repeating itself three times which is the maximum.
