That is a very simple mathematics question.5.39.217.76! j! p0 ?% k9 A
Let x = Male, y = Female, z = Child
: h" v5 u( q8 Z1 v4 m' O3 w公仔箱論壇6x + 3y + z/2 = 100 Formula 1
+ G3 H" l$ K& U$ T/ ~3 K公仔箱論壇x + y + z = 100 Formula 25.39.217.76+ u3 X) E, E8 v5 o
Simplify Formula 2 into z, we get z = 100 - x - y Formula 35.39.217.76$ }& e r6 M9 {$ R3 F e) f, Z
Sub Formula 3 into Formula 1, we get 6x + 3y + ( 100 - x - y )/2 = 100 Formula 4
: F0 j% }8 t' o$ _ t0 N# ]) }3 y; Btvb now,tvbnow,bttvbFormula 4 can change into 11x + 5y = 100 Formula 5tvb now,tvbnow,bttvb6 j* \& D) h& U0 m; m% v9 C' }
In Formula 5, x can only be 0 - 9, otherwise y will be negative number which we dont want.tvb now,tvbnow,bttvb' E* d! S2 d! s% {
And between 0 and 9, only 0 can give me a single number of y. So, x has to be 0 and y have to be 20. Then put x and y back to formula 1, we get z = 80.公仔箱論壇* c5 p: N- b. y
Eventually, the answer is 20 female and 80 children and no male. |
發表於 2007-10-13 05:08 PM
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