31. In the speed example below for instance, the arithmetic mean of 50 is incorrect, and too big. 32. The arithmetic mean of the many ages proclaimed by actress Melanie Griffith seems to be about 44. 33. Probably the best known weighted mean is the weighted arithmetic mean , usually simply called the weighted mean. 34. :3 ) For data which is not symmetrically distributed, like incomes and wealth, an arithmetic mean is meaningless. 35. If, this is equal to the exponential of the arithmetic mean of the natural logarithms of the numbers: 36. However, in practice and in the definition of MOS, it is considered acceptable to calculate the arithmetic mean . 37. The midpoint is just a special case of an arithmetic mean where you have two terms .-- "' 38. Arithmetic mean then must be zero.39. Note this is less than the arithmetic mean of the population size, which in this example is 126.7. 40. The arithmetic mean between 30 ? and 77 ? is 53.5 ?; the geometric mean is 48 ?.