Originally posted by knptmug at 2005-4-20 09:47 PM:% K- } z# m% n- f: H! P# B! P" g
set small watermelon: x, middle watermelon y and big watermeton z 7 v" i* i' H) u( o `6 d7 `; P& }8 ^3 V, _% M
two simultaneous equations are set up: " S/ A4 a6 m* E( U: `1 F0.5x+2y+5z=50 (1) 1 ^" o. g6 E; z( Sx+y+z=50 (2)+ C4 n0 y; L3 g7 [
Equation(1) means that the total amount paid is equal t ...
0 o' ^% R& v& l% z+ k0 b% f1 U
:lol::lol:5 j s1 o) e) F0 ~; @( u8 }
楼主的标题就是给你写的!; ~+ _$ Y7 F6 Z, G
你看看我们智力超群的同学们回答的都多好啊!