NO.PZ2018062016000048
问题如下:
Peter bought a security for $55 in year 1, $60 in year 2, $64 in year 3, $70 in year 4. The harmonic mean of the price will be:
选项:
A.61.77.
B.25.
C.37.04
解释:
A is correct. The harmonic mean : 4/[(1/55) + (1/60) + (1/64) + (1/70)] = 61.77
请问这道题如果知道价格,求价格的geometic mean怎么求呀?