Originally posted by knptmug at 2005-4-20 09:47 PM:" b- l/ r+ c% U' H( b: M8 F
set small watermelon: x, middle watermelon y and big watermeton z8 Z6 V L; a5 e1 G
/ i& L8 ]. W8 a' mtwo simultaneous equations are set up:0 \) d2 N7 j8 X/ [- _
0.5x+2y+5z=50 (1)& ?& H* F& w% J/ b# E& [6 l
x+y+z=50 (2) 7 A! N. X: l% Y* G0 C6 vEquation(1) means that the total amount paid is equal t ...
8 @8 ` a7 B. R# z% g:lol::lol:% J9 ?* V# E' \2 y# `+ O" y# n
楼主的标题就是给你写的!& L) z" I' r, G# x/ C# U: N# N
你看看我们智力超群的同学们回答的都多好啊!