※ 引述《kororoDX (軍曹)》之銘言：
: 有10隻兔子，合計共有50根蘿蔔，每隻兔子有的數量不一定，
: 現在任取四隻兔子，其擁有的蘿蔔數量必定不大於24，請問
: 每隻兔子最多有幾根蘿蔔?
: 答案是9
: 這是出現在不等式裡面的題目
: 請問其解法為何?
n_1 <= n_2 <= ... <= n_{10}
n_1 + n_2 + ... + n_{10} = 50
and A = n_7 + n_8 + n_9 + n_{10} <= 24
however, A = n_7 + n_8 + n_9 + n_{10} >= 50/10 * 4 = 20
denote B = n_1 + n_2 + ... + n_6
(i) A=20, B=30
then n_7<=20/4=5, n_6>=30/6=5
max n_{10} occurs at n_7=n_8=n_9=n_{10}=5
(ii) A=21, B=29
n_7<=21/4=5.25, n_6>=29/6=4.833..
n_7=5, n_6=5
max n_{10} occurs at n_7=n_8=n_9=5, n_{10}=6
(iii) A=22, B=28
n_7<=22/4=5.5, n_6>=28/6=4.66..
max n_{10} occurs at n_7=n_8=n_9=5, n_{10}=7
(iv) A=23, B=27
n_7<=23/4=5.75, n_6>=27/6=4.5
max n_{10} occurs at n_7=n_8=n_9=5, n_{10}=8
(v) A=24, B=26
n_7<=24/4=6, n_6>=26/6=4.33....
max n_{10} occurs at n_7=n_8=n_9=5, n_{10}=9
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