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wc2005
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wc2005
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All that means is we could both be wrong!

wc2005
Makes sense to me. Thanks for your help!!!
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jallenmorris

DURGESH...AM I RIGHT?

i think you are right on spot...

this is actauuly a question about xy plane and || lines disguised as complex "demand function"..... you've nailed it
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Thanks durgesh - i saw you browsing the forums and I trust your Quant abilities.
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wc2005
The equation for a linear demand function is:

D(p) = 10,000 – 60p

Due to a decline in demand the demand function shifts so that its graph is parallel to the graph of the original function and yields a demand of 2,500 when the price is $100. What is the demand when the price is $80?

Any thoughts? Thanks!

when we say parallel slope must be equal
hence consider :

D1(p)=y-60p
applying given conditions :
2500=y-100p
y=2500+100p
hence,
D1(p)=2500+100p-60p=2500+40p
at p=80,
D1(80)=2500+40(80)=2500+3200=5700
Demand is 5700
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spriya
wc2005
The equation for a linear demand function is:

D(p) = 10,000 – 60p

Due to a decline in demand the demand function shifts so that its graph is parallel to the graph of the original function and yields a demand of 2,500 when the price is $100. What is the demand when the price is $80?

Any thoughts? Thanks!

when we say parallel slope must be equal
hence consider :

D1(p)=y-60p
applying given conditions :
2500=y-100p
y=2500+100p
hence,
D1(p)=2500+100p-60p=2500+40p
at p=80,
D1(80)=2500+40(80)=2500+3200=5700
Demand is 5700
sorry silly mistake :( :roll:
D1(p)=y-60p
2500=y-6000 => y=8500
D1(p)=8500-60p
D1(80)=8500-60(80)=8500-4800=3700
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No problem. That's what the forum is for. We make the silly mistakes here so we don't make them when it counts toward our GMAT score.

spriya
spriya
wc2005
The equation for a linear demand function is:

D(p) = 10,000 – 60p

Due to a decline in demand the demand function shifts so that its graph is parallel to the graph of the original function and yields a demand of 2,500 when the price is $100. What is the demand when the price is $80?

Any thoughts? Thanks!

when we say parallel slope must be equal
hence consider :

D1(p)=y-60p
applying given conditions :
2500=y-100p
y=2500+100p
hence,
D1(p)=2500+100p-60p=2500+40p
at p=80,
D1(80)=2500+40(80)=2500+3200=5700
Demand is 5700
sorry silly mistake :( :roll:
D1(p)=y-60p
2500=y-6000 => y=8500
D1(p)=8500-60p
D1(80)=8500-60(80)=8500-4800=3700
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spriya
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jallenmorris
No problem. That's what the forum is for. We make the silly mistakes here so we don't make them when it counts toward our GMAT score.



when we say parallel slope must be equal
hence consider :

D1(p)=y-60p
applying given conditions :
2500=y-100p
y=2500+100p
hence,
D1(p)=2500+100p-60p=2500+40p
at p=80,
D1(80)=2500+40(80)=2500+3200=5700
Demand is 5700
sorry silly mistake :( :roll:
D1(p)=y-60p
2500=y-6000 => y=8500
D1(p)=8500-60p
D1(80)=8500-60(80)=8500-4800=3700[/quote]
correct :|



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