maths (1 Viewer)

[mouse]

help!

equation is:

4800 - Y = 4 [ 9000/P - .5Y ] .

answer is: Y = 1600 + 12000/P .

please show me the steps for getting the answer.

thanks!

 

[kpq_sniper017]

Somehow (dunno if it's me), I don't understand the equation.
What's the "- .5Y" mean?
Is it a typo, and meant to be - 5Y, or ½Y??

 

[Affinity]

it's probably some model for price of something and income

mouse: where's the question?

 

[Collin]

.5Y = 0.5Y = 1/2Y (95% of the time) Some people just tend to write is without the 0 in front of the decimal point. Don't do that mouse, it's a bad habit!

 

[mojako]

see this "picture"...

 

[mouse]

ok thanks guys i now understand.

well i need help on this one, it's so hard.

how are these possible:

(.4 + .1) / (.4 + .2) = 2 1/3

and

140/1 = .5Y - 10(.1) = 282

they are two seperate problems.

thanks!

 

[kpq_sniper017]

Originally posted by mouse
ok thanks guys i now understand.

well i need help on this one, it's so hard.

how are these possible:

(.4 + .1) / (.4 + .2) = 2 1/3

and

140/1 = .5Y - 10(.1) = 282

they are two seperate problems.

thanks!

can i just ask a few questions mouse?
1. what year are you in and what level of maths are you doing?
2. which textbook are you getting these questions from?

it might help us answer ur questions.
the ones u just posted don't make much sense to me at all.

anyone else got any ideas???

 

[George W. Bush]

he's doing economics at uni from what i can gather

 

[kpq_sniper017]

Originally posted by George W. Bush
he's doing economics at uni from what i can gather

if he's doing economics at uni:
1. why is he posting in the hsc maths section?
2. is the question supposed to make sense, even in uni economics?

 

[George W. Bush]

there's a simple answer to both questions....

 

[mojako]

Originally posted by mouse

how are these possible:

(.4 + .1) / (.4 + .2) = 2 1/3

and

140/1 = .5Y - 10(.1) = 282

OMG... this is starting to get a bit ridiculous in a way... or weird at least... (and since you put this in a maths extension forum).

The first equation is absolutely impossible UNLESS you either:
1. make a new set of rules governing the operations of addition and division
2. make a new definition on the meaning of symbols, for example, "/" doesn't mean "divided by"
3. do both point 1 and point 2

Anyway, let's make it clear of why it's not possible:
(.4 + .1) / (.4 + .2) = 2 1/3
0.5 / 0.6 = 2 1/3
0.5 / 0.6 = 7 / 3
5 / 6 = 7 / 3
BUT, assuming you don't do any of points 1-3 above, 5 / 6 is not equal to 7 / 3. Quite easily, 5 / 6 is less than 1 while 7 / 3 is more than 1.

Now, the second equation:
140/1 = .5Y - 10(.1) = 282
I prefer to break this down to three sub-equations:
140/1 = .5Y - 10(.1)
140/1 = 282
.5Y - 10(.1) = 282
The first sub-equation is possible for certain value of Y. So is the third sub-equation. However, we can deduce that the second sub-equation is not true, therefore the overall equation, 140/1 = .5Y - 10(.1) = 282, is not true and there is no solutions to it.

Do I make sense? Well, I'm just a bit bored at the moment so sorry if I seem too wordy...

 

[kpq_sniper017]

Originally posted by George W. Bush
there's a simple answer to both questions....

and what are those answers?