题目
A portfolio manager invests €5,000 annually in a security for four years at the prices shown in the following exhibit.「huixue_img/importSubject/1564548694504771584.png」The average price paid for the security is closest to:
选项
A.harmonic mean of €76.48.
B.geometric mean of €77.26.
C.arithmetic average of €78.00.
答案
A
解析
： A is correct. The harmonic mean is appropriate for determining the average price per unit. It is calculated by summing the reciprocals of the prices, then averaging that sum by dividing by the number of prices, then taking the reciprocal of the average: 4/[(1/62.00) + (1/76.00) + (1/84.00) + (1/90.00)] = €76.48. ： A正确。调和平均数适用于确定每一单位的平均价格。它的计算方法是将价格的倒数相加;然后除以价格的平均数;最后，取平均值的倒数。 4/[(1/62.00) (1/76.00) (1/84.00) (1/90.00)] = €76.48.