Originally posted by knptmug at 2005-4-20 09:47 PM: . r6 v/ x6 O$ W) m& Y4 w {set small watermelon: x, middle watermelon y and big watermeton z % F/ r" `2 i% i t+ M. q! E0 q. V, x4 V# Z
two simultaneous equations are set up:) u2 p% \& E! G/ Z7 @" o
0.5x+2y+5z=50 (1) , m/ S- B3 g- f Y: ~5 w/ n7 Rx+y+z=50 (2): V7 z2 X$ w% W
Equation(1) means that the total amount paid is equal t ...
" Q6 e. S1 i/ k:lol::lol:- m |/ ~5 E( k4 d% q$ h
楼主的标题就是给你写的! 6 ~4 \& B$ A; e你看看我们智力超群的同学们回答的都多好啊!