Originally posted by knptmug at 2005-4-20 09:47 PM:9 i/ o8 H" t) {+ t
set small watermelon: x, middle watermelon y and big watermeton z7 {5 j" C. w3 x% q# m) B
8 m! f7 `% U/ K$ ctwo simultaneous equations are set up: & Z6 P- f5 e$ D8 k/ q; L! x0.5x+2y+5z=50 (1) % S) G2 m! y- y# d I8 ~, ]x+y+z=50 (2) 4 q# A" O3 A8 SEquation(1) means that the total amount paid is equal t ...
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:lol::lol:9 B4 G& s- C% m/ z7 X
楼主的标题就是给你写的! X. u1 X7 F" _% E2 e你看看我们智力超群的同学们回答的都多好啊!