Question 1042611
<pre>c chicken dinners,
s salmon dinners, 
t steak dinners</pre>

{{{system(c+s+t=45,c=(s+t)/2,9c+12s+15t=525)}}}, the accounting of dinners, relation between c and s, and cost.   Solve the system.




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Simplify the cost equation as a first step.  Divide members by 3.
{{{3c+4s+5t=175}}};
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System may be adjusted to {{{system(c+s+t=45,2c=s+t,3c+4s+5t=175)}}}.