VCE General & Further Maths Question Thread!

[AngelWings]

Yes, it's the same units for the mean.
Overall: Just remember to check your units, then apply common sense.
It shouldn't be much harder than that. 
(I checked the decimal place thing a few weeks back. Unless specified and it doesn't HAVE to be whole e.g. time, it's typically 2 dp for the final answer, EXCEPT in the case you're doing an r or r^2 value. Or at least, that's what I recall... hm.)

[Splash-Tackle-Flail]

Thank you again, you have no idea how long this has been troubling me!

[AngelWings]

No worries. Oh and to clarify my last post, r and r^2 values should actually be 4 dp, unless something states otherwise.

[plato]

A mean value, or a predicted value, can be a decimal. For instance, the average household size in Australia in 2011 was 2.6 people. (Ref: http://www.aifs.gov.au/institute/info/charts/households/#havsize)

When an answer should be a whole number, then do NOT just automatically round to the nearest whole number. Read the question to see if it tells you what to do. Look for phrases such as "at least" or "more than" or "no more than" or "fewer than". Sometimes you may have to round an answer like 146.34 up while at other at other times you would round it down.

If the answer to a question is truly a decimal, you can expect the question to dictate the number of decimal places required unless the decimal number is exact. An answer of 4.6250000000 must be written as 4.625 unless there is an instruction to round off to a stated number of decimal places. An answer of 4.6250423897761............ etc would have the required number of decimal places dictated in the question.

The value of r and r² should be rounded as dictated by the question. While this has often been four decimal places, you must check this each time.

[spectroscopy]

yo i got a linear question
a herbalist wishes to prepare a mixture from two herbs, A and B. The mixture costs $6 per kilogram. If herb A costs $5 per kilogram and herb B costs $8 per kilogram, and 60 kilograms of mixture is to be prepared, how many kilograms of each herb should be used?

[keltingmeith]

http://www.atarnotes.com/forum/index.php?topic=142314.msg761176.msg#761176

This question has already been answered in the link above.

[spectroscopy]

Re: Further Question Thread!

This question has already been answered in the link above.

oh cheers !

[LiquidPaperz]

you probably dont need the question for this. But with transition matrix why, (when the formula is Sn = T^nSo) if its 4th week dont you do T to the power of 4 and not 3. I remember my teacher saying something about this in class but i didnt listen, cause i was doing something else, but doing checkpoints i havent seen this come up.

[plato]

Define S_n as the nth state matrix.

When the initial state matrix is labelled S₀ , it occurs at n = 0.
The second term is then, S₁, is at n = 1 and is given by
S₁ = TS₀
and continuing,
S₂ = TS₁=T²S₀
etc
and so S_n =TⁿS₀

BUT, if the initial state matrix is labelled S₁, which occurs at n = 1,
then S₂ = TS₁
and continuing,
S₃ = TS₂=T²S₁
etc
and so S_n =T^n-1S₁

Can you see what would happen if the initial state matrix was labelled S₂₀₁₄ ?

[LiquidPaperz]

heres the question, it said initially so i assumed no time had elapsed

[plato]

I would call the initial state matrix S₀ for this question, although there is a discrepancy between the numbers for the Airstart and Airfleet customers between the question and the answer.

I think the answer to the question should be
S_n = Tⁿ x S₀
where S_n is the state matrix after n transitions.
and the relevant matrices for T and S₀ substituted.

The answer given is only the calculation that would produce S₁, the state after the first transition.

[LiquidPaperz]

is the answer wrong here? i got c

[keltingmeith]

It's C, answers wrong.

[kinslayer]

Whoever wrote the answers switched A and B around, hehe

[Billion]

Business Maths Question - help appreciated.

James and Jamie have just finished repaying a 5 year, $8000 reducing balance loan.
During the first year interest was debited monthly at 8.5% p.a.; during the next 2 years the rate fell to 8% p.a. but rose to 8.3% p.a. for the remaining period of the loan.
Before signing their contract James and Jamie were also given the option of fixing the interest rate at 8.25% p.a. (debited monthly) for the term of the loan.
By considering the total amount of interest that they paid, determine whether James and Jamie made the right decision in choosing the variable interest rate for the loan rather than the fixed rate.

Answers

Fixed: Interest = $1790.20
Variable: Interest = $1784.51 so correct decision is the variable, by $5.69