That is a very simple mathematics question.* _& |$ E, e& b2 ?3 G( D
Let x = Male, y = Female, z = Child 0 h0 X# y0 N/ G0 Z# j6x + 3y + z/2 = 100 Formula 1 ) h* d( u; b6 u- x) o. _# px + y + z = 100 Formula 2$ ?' ]1 ~, f/ [* c
Simplify Formula 2 into z, we get z = 100 - x - y Formula 3 ! Z6 s3 T, E0 q5 j( y. v0 T' j5.39.217.77Sub Formula 3 into Formula 1, we get 6x + 3y + ( 100 - x - y )/2 = 100 Formula 4tvb now,tvbnow,bttvb; w" L0 L0 v: K# M6 y) ^* r
Formula 4 can change into 11x + 5y = 100 Formula 5% @* k& z* z9 J* }" @
In Formula 5, x can only be 0 - 9, otherwise y will be negative number which we dont want.3 H1 f) h0 u% C( W
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. : k. x4 v: m2 K" J# ^; CEventually, the answer is 20 female and 80 children and no male.作者: alan1234 時間: 2007-10-14 12:19 AM 標題: two answers
原帖由 twinsdragon 於 2007-10-13 05:40 PM 發表 TVBNOW 含有熱門話題,最新最快電視,軟體,遊戲,電影,動漫及日常生活及興趣交流等資訊。9 |0 g( y. B6 y5 x. E
11x + 5y = 100 Formula 5
tvb now,tvbnow,bttvb. b$ v) e) d* b& R2 {) B2 G a
11X must be 0 or multiple of 5 9 M5 u( }& c8 M3 u7 Ethat meanz x must be 0 or 5作者: manstein 時間: 2007-10-15 08:28 PM