Re: [計量] The 20 people at a party are divided ...
※ 引述《yauu (真無雙亂舞)》之銘言：
: 1. 0<p<1
: the greatest value of p(1-p) : 1/2
: 2. The 20 people at a party are divided into n mutually exclusive
: groups in such a way that the number of peopel in any group does not
: exceed the number in any other group by more than 1.
: the value of n if at least one of the groups consists of 3 people : 6
: 謝謝!!
1. p(1-p) = p - p^2 = -(p-1/2)^2 + 1/4 , 所以有最大值的情況發生在p = 1/2 ,
p(1-p) = 1/4，因此選B
2. 一個group裡有3個人，按照題意，其他group裡只能含3個人 or 4個人，因此
3個人的group有4個，4個人的group有2個，n為6，選C
請大家多多指教了。
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