Originally posted by knptmug at 2005-4-20 09:47 PM:$ @, [( [5 G- u# n3 S2 L$ n
set small watermelon: x, middle watermelon y and big watermeton z+ D n" |- ~. E: T0 c
, O( s0 h0 I8 H( d9 W9 k$ f! I: i
two simultaneous equations are set up:( F j' j; e( i1 R2 }( X4 Q" |3 m
0.5x+2y+5z=50 (1)( w$ g& \ Y8 w0 N* u: W0 v2 |
x+y+z=50 (2) 1 K$ U/ S5 J( _6 \' I7 UEquation(1) means that the total amount paid is equal t ...
5 x. F( L7 {; p
:lol::lol:1 Y% h7 S: l' [
楼主的标题就是给你写的!1 C5 x' ?. v5 e
你看看我们智力超群的同学们回答的都多好啊!