Originally posted by knptmug at 2005-4-20 09:47 PM: ; Y) b( x# G* c# b& R4 Z$ z5 Kset small watermelon: x, middle watermelon y and big watermeton z 3 {! K) V0 C5 ?6 ^5 s! H' P" j! [5 U& _: [6 I6 q
two simultaneous equations are set up:: G5 U9 G3 f% o) W/ N) w
0.5x+2y+5z=50 (1) + Z( K* b- T; D/ h! ~: |x+y+z=50 (2) . T& ~8 S: _9 H% bEquation(1) means that the total amount paid is equal t ...
1 k! @7 n. |8 i( V; A; X3 R( t:lol::lol: . q4 m' a& G4 J9 s' M1 S楼主的标题就是给你写的!5 M8 q; }; [& t1 t2 r
你看看我们智力超群的同学们回答的都多好啊!