Math Short Notes: Average

 Average  

- General Formula:  

 Average = (Sum of all observations)/(Total number of observations)

- Sum of Observations:  

 Sum = Average x Number of observations

- Arithmetic Progression (AP):  

 Average = 1/2 x (First Term + Last Term)

- Combined Average:  

 Combined Average = (n_1A_1 + n_2A_2)/(n_1 + n_2)