Originally posted by knptmug at 2005-4-20 09:47 PM: , V) V+ P5 l! S) `+ |; A _9 ^set small watermelon: x, middle watermelon y and big watermeton z * X2 A/ N- U+ |4 `) D# e% o. t- Z+ ?2 v" P* U
two simultaneous equations are set up:' A, n$ b; {, H& c5 D4 a
0.5x+2y+5z=50 (1) 5 t& B3 C; O: k/ c& H- fx+y+z=50 (2)3 R0 o3 { P" Z. |0 G
Equation(1) means that the total amount paid is equal t ...