Originally posted by knptmug at 2005-4-20 09:47 PM:, b V D/ k- N/ I
set small watermelon: x, middle watermelon y and big watermeton z$ G- k; o3 M: p/ ?8 \; Z7 ]
~" O! c) k1 C5 C; ^two simultaneous equations are set up:* V# Z2 d. K, ~) L
0.5x+2y+5z=50 (1); `4 v0 b! e4 n* _& A/ h5 s+ U5 t
x+y+z=50 (2): V* W9 \' e) j. i
Equation(1) means that the total amount paid is equal t ...
; V; B/ i T+ L4 V2 [ p
:lol::lol:" p4 {( o5 {! A4 {! m" K1 Z
楼主的标题就是给你写的!/ e4 z+ l7 { y; A6 n2 P9 z
你看看我们智力超群的同学们回答的都多好啊!