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View Full Version : Help with constraints. Reward.


Failpailirl
09-18-2011, 11:13 PM
Can somebody help me out with constraints? i have no idea how to do them and i have a word problem on them due tommorow. Willing to give a 3m rsgp reward to the first person to solve this if solved tonight before 11 PM EST, i need this ASAP.

A gold processor has two sources of gold ore, source A and source B. In order to keep his plant running, at least three tons of ore must be processed each day. Ore from source A costs $20 per ton to process, and ore from source B costs $10 per ton to process. Costs must be kep to less than $80 per day. Moreover, Federal Regulations require that the amount of ore from source B cannot exceed twice the amount of ore from source A. If ore from source A yields 2 oz. of gold per ton, and ore from source B yields 3 oz. of gold per ton, how many tons of ore from both sources must be processed each day to maximize the amount of gold extracted?

This is what i have so far, i am not sure if its right. I have to graph this and i am not quite sure what to do after this step even if i did get this right (which i probably didint)

A+B>3
20A+10B<80
A>2B
bolshak25
09-18-2011, 11:39 PM
i believe 3a 1b

E:nvm i just solved it
Failpailirl
09-18-2011, 11:41 PM
i believe 3a 1b

for what? i have to write 3 constraints, and an objective function.
bolshak25
09-18-2011, 11:53 PM
your first and third constraint should also have equal to.

and the equation

max f(x)=2a+3b

unless you need that in a different format?
Failpailirl
09-18-2011, 11:57 PM
your first and third constraint should also have equal to.

and the equation

max f(x)=2a+3b

unless you need that in a different format?

can you pm me your msn or something?
bolshak25
09-18-2011, 11:59 PM
sent
Failpailirl
09-19-2011, 12:10 AM
bolshak help me figure this out and solve it! thanks. will be paying him. somebody please close this.
Wizzup?
09-19-2011, 09:33 AM
Perhaps it would be nice if we would all see how it was solved? :)
bolshak25
09-19-2011, 08:06 PM
yes of course!
his constriants are right.
A+B>=3
20A+10B<80
A>=2B

as for finding the objective function, the part about how much ore is extracted gives that.

max 2a+3b

for graphing, you have to take the equations and make it so a is alone on one side.
a>=-b+3
a<-.5b+4
a>=2b
a is y b is x
when you graph that, there is a shaded region. those are all the possible solutions.
then you just find the best solution which is
3 of a and 1 of b which is 9 oz of gold at a cost of $70