Question 166298
I am having problems mathematically showing this 

but we know that{{{10<=h<=40}}}
and.............{{{30<=d<=70}}}
and.............{{{h+d<=90}}}    where h= # of hamburgers and d= # of hotdogs.

when one takes the max # of hamburgers which make more profit
than dogs we have 40 burgers meaning we can only have 50 dogs
because {{{h+d<=90}}}...so .33(40)+.21(50)= $23.70 profit....now if you take the maximum # of dogs you would have 70 meaning you can only have 20 hamburgers again due to {{{h+d<=90}}}. so we have .33(20)+.21(70)= $21.30
profit.  anything combo of hamburgers and hotdogs between these maximums also render profits that are between those 2 profits so my opinion is that this is the correct answer.{{{40-hamburgers-and-50-hotdogs}}}