Originally posted by knptmug at 2005-4-20 09:47 PM:) F! {) u- G, b0 u* c
set small watermelon: x, middle watermelon y and big watermeton z $ y# C6 ~* Z. P6 w% Y3 [5 ~9 Y7 ^- ?8 _: s* g
two simultaneous equations are set up: % Y% \6 `* ?* ~+ g7 M5 _, \0.5x+2y+5z=50 (1)% }0 }$ T# Q2 B0 a7 G9 w
x+y+z=50 (2)" n" b) b. C+ L' d- m' D
Equation(1) means that the total amount paid is equal t ...
( U Y5 \' _4 B. W0 k$ h
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