Arithmetic mean Average

the common type of average arithmetic mean. if n numbers given, each number denoted ai (where i = 1,2, …, n), arithmetic mean sum of divided n or

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{\displaystyle am={\frac {1}{n}}\sum _{i=1}^{n}a_{i}={\frac {1}{n}}\left(a_{1}+a_{2}+\cdots +a_{n}\right)}

the arithmetic mean, called mean, of 2 numbers, such 2 , 8, obtained finding value such 2 + 8 = + a. 1 may find = (2 + 8)/2 = 5. switching order of 2 , 8 read 8 , 2 not change resulting value obtained a. mean 5 not less minimum 2 nor greater maximum 8. if increase number of terms in list 2, 8, , 11, arithmetic mean found solving value of in equation 2 + 8 + 11 = a + a + a. 1 finds = (2 + 8 + 11)/3 = 7.