Question 979048
Price wanted:  20 pesos/kilogram


Following your description very strictly:


Available:
*   40 kilograms at (18/40) pesos/kg
*   unknown kilograms at (28/u) pesos/kg
-
The variable u, is how much of the {{{28/u}}} priced rice to use.



{{{MONEY/MIXTURE=PRICE}}}


{{{highlight_green((18+28)/(40+u)=20)}}}


{{{46/(u+40)=20}}}
{{{23/(u+40)=10}}}
{{{23=10(u+40)}}}
{{{23=10u+400}}}
{{{10u=23-400}}}
{{{10u=-377}}}
{{{highlight_green(u=-37.7)}}}------obviously makes no sense.  The wording of the description is important.  Your description as shown is unreliable as written.  COST and PRICE do not mean the same thing.