ATAR Notes: Forum
VCE Stuff => VCE Mathematics => VCE Mathematics/Science/Technology => VCE Subjects + Help => VCE General & Further Mathematics => Topic started by: Hye on August 06, 2010, 08:44:20 pm
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A mining company is required to move 200 workers and 36 tonnes of equipment by air. It is ble to charter 2 aircraft: a hawk, which can accommodate 20 workers and 6 tonnes of equipment, and an Eagle, which can accommodate 40 workers and 4 tonnes of equipment. Let x denote the number of trips made by hawk aircraft and y denote the number of trips made by the Eagle aircraft.
write down the constraints that x and y must satisfy.
20x+40y (is it larger or smaller than and equal to?) 200
6x+4y (is it larger or smaller than and equal to?) 36
not sure which sign it is?
Thanks
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smaller than cause the aircraft can hold only that much so it cant be more but only less. :S
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smaller than cause the aircraft can hold only that much so it cant be more but only less. :S
yeah i went with that as well. But the answer says that
20x+40y is larger than and equal to 200
6x+4y is larger than and equal to 36
(sorry i don't know how to use latex)
thanks
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also for another question i encountered the same problem.
'An outdoor manufacturer has 520 metres of polarfleece material.'
'672 hours available'
Which signs would that be? ( If you need the whole question i'll type it if you want, its just a pain to type these lengthy questions up)
Thanks
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its a sign that the textbook is crap...no offence D:
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Haha this is from the essentials textbook :}
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also for another question i encountered the same problem.
'An outdoor manufacturer has 520 metres of polarfleece material.'
'672 hours available'
Which signs would that be? ( If you need the whole question i'll type it if you want, its just a pain to type these lengthy questions up)
Thanks
it would be
ax + by <=520
cx + dy <= 672
When its greater than or equal to, it's likely to ask for minimum cost
When its less than or equal to, it's likely gonna ask for the maximum profit
So if you're unsure look at if it asks you to find cost or profit and it should determine it
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A mining company is required to move 200 workers and 36 tonnes of equipment by air. It is ble to charter 2 aircraft: a hawk, which can accommodate 20 workers and 6 tonnes of equipment, and an Eagle, which can accommodate 40 workers and 4 tonnes of equipment. Let x denote the number of trips made by hawk aircraft and y denote the number of trips made by the Eagle aircraft.
write down the constraints that x and y must satisfy.
20x+40y (is it larger or smaller than and equal to?) 200
6x+4y (is it larger or smaller than and equal to?) 36
not sure which sign it is?
Thanks
Think about it for the first one. It is required to lift a minimum of 200 workers so definitely its greater than or equal to because if it were less than the required region would be taking into account 199 workers, 198 and so on... something you don't want.