Originally posted by knptmug at 2005-4-20 09:47 PM:1 N! D7 F% f) k: a. x
set small watermelon: x, middle watermelon y and big watermeton z ' s1 o8 t2 T- ~8 c1 `5 z3 p0 ?( k2 k, @" n, o; N
two simultaneous equations are set up: 6 i% T, s! G$ ?$ t& j) Y* V/ _0.5x+2y+5z=50 (1)0 B% v. ]7 O# K6 B5 t! D
x+y+z=50 (2) " _$ r5 x3 {' w( b$ ~; ~; S$ VEquation(1) means that the total amount paid is equal t ...
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:lol::lol: - m9 A3 N2 _; U. ]楼主的标题就是给你写的!# c8 Y. l6 {5 s% x+ M# k z$ n
你看看我们智力超群的同学们回答的都多好啊!