Wikipedia:Reference desk/Archives/Mathematics/2008 June 11

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June 11[edit]

Accounting Formula[edit]

A machine costing $ 2,187 is estimated to have a scrap value of $128 at the end of 7 years.It is decided that a constant rate of depreciation on a diminishing value will be used.Rate is given by the formula.

R=1-N/(S/C) N is the number of the years. S is the scrap value and C is the Cost.

Question: Please let me know how to slow this problem? Thanks

Lanka..

There doesn't appear to be a question in there, but if you assume that the question is "what is the rate of depreciation?" then all you need to do is perform the appropriate substitutions.
N = number of years = ?
S = scrap value = ?
C = initial cost = ?
Once you can replace the question marks with numbers, put those numbers into the place of the symbols in the formula, and calculate that to give you R. Confusing Manifestation(Say hi!) 04:42, 11 June 2008 (UTC)[reply]
I don't think I agree with that formula. See Depreciation#Declining-Balance Method. Zain Ebrahim (talk) 12:48, 11 June 2008 (UTC)[reply]
I don't agree with the formula either. That rate doesn't seem to make you end up with the scrap value after N years... It may just be written down wrong (hence the unusual notation of a fraction inside a fraction) - should that first slash be an n-th root symbol? I think it works then. --Tango (talk) 13:29, 11 June 2008 (UTC)[reply]
Yeah, it will work in that case because it would solve S = C(1-R)^N. Zain Ebrahim (talk) 13:38, 11 June 2008 (UTC)[reply]

Not only is this as routine as it gets, but the person who posted it doesn't seem to have paid enough attention to what he was writing to notice that he forgot to include the actual question. The way that usually happens in that the question appears at the top of a list of assigned problems, each bearing a number, and the person simply copies what it says under "#6" and doesn't understand that the question at the top is needed as well. I don't think the person who posted this cares about the solution to the problem or even has the foggiest idea what the problem is. He just wants to turn in an answer to a homework assignment, without knowing what it says. Michael Hardy (talk) 16:37, 11 June 2008 (UTC)[reply]

The person wrote "Question: Please let me know how to slow this problem?" (and I think it's safe to assume the meant "solve" not "slow"), so what more do you guys want? --LarryMac | Talk 17:46, 11 June 2008 (UTC)[reply]
We want to know what the problem is. There isn't actually a problem stated, just a load of facts (one of which appears to be complete nonsense due to an inaccurate transcribing of the notation). Assuming the problem is "find the rate of depreciation", it's just a matter of substituting values into a formula and if someone doing economics can't work out how to do that, it suggests they haven't even tried to do the question before coming here. --Tango (talk) 18:50, 11 June 2008 (UTC)[reply]

Refer to my Question on June 11.

This Accounting Question I got from: ARCO- Accountant/Auditor 9th edition Pg.44

28. A machine costing $ 2,187 is estimated to have a sceap value of $128 at the end of seven years. It is decided that a constat rate of depreciation on a diminishing value will be used. Rate is given by the formula:

R= 1-N/(S/C)

Where N is the mumber of years, S is the scrap balue and C is the cost . The rate will then be (A) 50% (B) 40% (C) 66.7% (D) 33.3%

The answet is (D) as a book.

I'm preparing for the City test. This not a home work,also several times I have tried this,and can't get. Please help me to get answer clear way. Lanka

Well, yes, the answer is D. Have you read our replies above? For a start, you have the formula wrong. It should be . Secondly, if you don't know how to substitute values into a formula, you should not to taking this kind of test, you need to go back and learn the underlying basic maths first. --Tango (talk) 22:30, 11 June 2008 (UTC)[reply]

Paired trinomial test?[edit]

I have a set of units, each of which can fall into one of three categories. I have data for each unit at two timepoints, t1 and t2. Is there a statistical test that will tell me if a significant number in, say, category A at t1 have moved to category B at t2? It feels to me like it's a three-category version of a paired sign test, but I have no idea how to define it. Confusing Manifestation(Say hi!) 05:33, 11 June 2008 (UTC)[reply]

It's not clear what your test desires. If the timepoints are independent, then a fixed fraction (on average) of those in A at t1 will be in B at t2 (the fraction being the time independent probability of being in B). If you want to test for this independence, what are you assuming about C? That is, would you consider only those which both started and ended in A or B (suggesting Fisher's exact test) or would your consider enlarging the implicit contingency table to include C (implying a higher dimension generalization of FET)? Baccyak4H (Yak!) 16:34, 11 June 2008 (UTC)[reply]
What is your null hypothesis?  --Lambiam 08:29, 12 June 2008 (UTC)[reply]

Development of geometry[edit]

ahhm,...!!!hello could u give a list of mathematicians that have help in development of geometry?,...plz. include the things they hav done n improving geometry!!!!tnx —Preceding unsigned comment added by 210.213.194.15 (talk) 11:06, 11 June 2008 (UTC)[reply]

Try list of geometers and Category:Geometers. Algebraist 11:42, 11 June 2008 (UTC)[reply]
Euclid contributed a few results to geometry, so he seems like the only rational place to start, in my opinion. He also popularized one of the longest played games throughout history, which still has left people still today sending proofs of angle trisection, circle squaring and cube doubling to chairs of math departments across the world GromXXVII (talk) 22:18, 11 June 2008 (UTC)[reply]

numbers[edit]

which numbers that dividible of 145? —Preceding unsigned comment added by 192.30.202.22 (talk) 18:51, 11 June 2008 (UTC)[reply]

anything of the form where Philc 0780 19:01, 11 June 2008 (UTC)
If you mean which natural numbers 145 is divisible by then it's 1, 5, 29, 145. PrimeHunter (talk) 19:20, 11 June 2008 (UTC)[reply]

subleading order[edit]

I need someone to explain something for me, because I could not find it in any article on wikipedia.

What is meant by the term "subleading order"?

For example,

"Show P(N)=1/ln(N). Assume N is large and ignore terms in your answer that are of subleading order in N."


130.113.172.112 (talk) 18:56, 11 June 2008 (UTC)[reply]

It means a term such that . -- Meni Rosenfeld (talk) 19:21, 11 June 2008 (UTC)[reply]