Originally posted by knptmug at 2005-4-20 09:47 PM:) s5 u) c" A4 W& P
set small watermelon: x, middle watermelon y and big watermeton z" e4 T- J$ H5 ]* v3 I3 d
! \4 x$ m% x0 `8 }2 E: W
two simultaneous equations are set up:) x1 g" L5 D) c4 c$ J
0.5x+2y+5z=50 (1)& c/ T& t* v1 _; J% _! s
x+y+z=50 (2)& d$ F3 p! Q& s: C+ `
Equation(1) means that the total amount paid is equal t ...