Originally posted by knptmug at 2005-4-20 09:47 PM:/ M& u+ b' X# z
set small watermelon: x, middle watermelon y and big watermeton z% j+ A0 j ?* Z* k+ F4 E
% ]7 K" R" R5 U2 m: \two simultaneous equations are set up:6 { S& o* o- i/ [8 n8 t, E# Z
0.5x+2y+5z=50 (1)3 B) ?2 \# |+ @9 |/ K5 o$ `
x+y+z=50 (2)& a1 r% R* z, i+ N# K! `
Equation(1) means that the total amount paid is equal t ...