F.3 Measures of Central Tendency(Means)
2008-11-19 7:04 am
The mean age of all players in a football team is 21. If the 35-year-old coach and the 51-year-old manager are included, the mean age of the team increases by 2. Find the total number of players in the football team.
回答 (1)
2008-11-19 7:19 am
✔ 最佳答案
Let n be the total number of players in the football team.
Total ages of players = 21n
(New mean age) - (Old mean age) = 2
[(21n + 35 + 51)/(n + 2)] - 21 = 2
(21n + 86)/(n + 2) = 23
21n + 86 = 23(n + 2)
21n + 86 = 23n + 46
-2n = -40
n = 20
Ans: There are 20 players.
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收錄日期: 2021-04-24 09:52:21
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