Question 966770
Variable quantities are the prices for the corn and potatos.

p, dollars per bag for potatos;
c, dollars per case for corn;


{{{system(3p+4c=40,5p+2c=34)}}}


Solve the system in any way you know.  Elimination method may be good for a start if you take the second equation and use as  {{{10p+4c=68}}}.