以下是引用wwwhahchn在2005-9-18 11:06:00的发言:
我怎么觉得应该是(v+w+x-y+z)/5呢??前面那些系数怎么来的???
2004年9月JJ
257.price change equal to the current day’s closing price minus the last day’s closing price, provide you the price changes for the five working days of a week as follows:v (price change) for Monday, w for Tuesday, x for Wednesday, (-y) for Thursday and z for Friday. Ask you the average price of the week.
解法:m1=v, m2-m1 = w, m3-m2 = x, m4-m3 = -y, m5-m4 = z.
所以(m1+m2+m3+m4+m5)/5 = (5v+4w+3x-2y+z)/5
3w,注意highlight的那句话,根据上面的式子,m1=v,m2=w+v.....然后加来的,嘻嘻
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