Questions having to do with financial mathematics. Please note that for questions in quantitative finance, quant.stackexchange.com is perhaps a better site.

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230 views

Profit and Loss calculation: Fake currency

A store buys an item for $\$50$. They price it then, at $\$80$ ($\$30$ profit margin). A customer buys the item from them with a fake $\$100$ note. The store returns $\$20$ to the customer. My ...
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1answer
171 views

How to compute ideal investment leverage ratio based upon volatility? [closed]

I want to compute the ideal investment leverage ratio based upon an investment's volatility. For example, if I had an investment that with 50% likelihood quadruples your investment on a given day ...
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1answer
5k views

How do you calculate “excess returns”?

(Although this is perhaps a very simple question, math-wise, it still has me puzzled so it's okay to ask for help here I guess. I really need to understand this, so any help is appreciated) First, ...
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19k views

Calculate gross salary when knowing the net salary and tax brackets

Assume the annually gross salary is $100,000. Tax brackets: 0 - 50K - 10% = 5K in taxes 50K - 70K - 20% = 4K in taxes 70K - $90K - 30% = 6K in taxes 90K and up - 40% = 4K in taxes The income tax ...
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98 views

Calculate breakeven when fixed revenue being added per month v/s cost

I am writing up a cost sheet for a product and I basically suck at math. Didn't know who else to turn to, so trying out Math exchange. So, I am planning to spend ...
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1answer
197 views

Binomial model of stock price

I've got a homework question which I think I have solved but am not certain if the answers are correct. The question goes like this: Consider a stock which has a 50% chance of increasing by 80% by the ...
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2answers
182 views

Stochastic/finance monte carlo question

When pricing a european option by monte carlo over 30 days for instance, what's the difference between one big 30 day jump vs 30 one day steps?
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1answer
25 views

Interest Accumulation - Geometric Sequence

Hello I have just worked a question in which I get an answer different to the answer in my book. The question states: If a person deposits 500 at the end of each month for 20 years at an AER of ...
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1answer
28 views

Where to find Geman 1995's proof on Changes of Numaraire?

Geman, H., El Karoui, N., Rochet, J.C. (1995) published paper "Changes of Numeraire, Changes of Probability Measures and Pricing of Options", on "Journal of Applied Probability " vol 32, pg 443-458. ...
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1answer
55 views

mortage with monthly payment - mathematical modeling

$Question:$ Suppose that $x_n$ is the amount owed on a mortgage after n years, $\$m$ is the monthly repayment and $r$ is the annual percentage interest rate charged on the amount of the mortgage ...
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1answer
46 views

How to calculate the ⌉ operator?

In a book about finance, the following formula appears: $$\large a_{10 \,⌉\, 0.04}$$ What is this ⌉ operator and how to read / calculate it?
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43 views

How to find the rate of interest?

Q. The simple interest in 3 yrs and the compound interest in 2 yrs on the same principal and at the same rate are 1200 and 832 respectively. Calculate the rate. What I've done: SI in 3 years = ...
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42 views

Actuarial Science FM Question

$$a(t)=Zt^2+Bt+1$$ If \$100 at $t=0$ grows to \$152 at $t=4$ and \$200 at $t=0$ grows to \$240 at $t=2$, what are $Z$ and $B$? Please show work. Also, what would \$1600 invested at $t=6$ grow to at ...
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1answer
162 views

Master degree require Matlab? [closed]

I'm devon. I'm in second year math integrated computer concentrate in statistic. I love math and I'm very interested in finance. So I'm planning to get the master degree in Financial Mathematic. What ...
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1answer
120 views

Calculate the yield rate on transaction

Problem:- 'A' is able to borrow $1000 from 'B' for one year at 8% effective and at the same time lend it to 'C' for one year at 10% effective. what is 'A's yield rate on this transaction? My ...
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1answer
779 views

Black-Scholes PDE to heat equation, nonconstant coefficients

Can someone provide me with details or a reference on how to transform the Black-Scholes PDE with nonconstant coefficients (i.e. $r=r\left(S,t\right)$, $\sigma=\sigma\left(S,t\right)$) to the heat ...
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2answers
23 views

In this situation, how to decrease the payout amount based on the “weighed” constituent parts?

Couldn't think of a better way to explain it in the title, my bad. This is a problem I'm running into in a programming project. Here's the situation: Say a partner is due to be paid $1000 for ...
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2answers
38 views

Percentage of capitalization

After how many years the deposited sum of K-euros will triple itself if the interest percentage of capitalization is 12%, the capitalization is annual.
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1answer
482 views

Converting an Annuity due to Annuity immediate

I'm working on the following problem at the moment while preparing for an exam. Find the present value of payments of 200 every six months starting immediately and continuing through four years from ...
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1answer
331 views

Help understanding confusing present value question (Theory of Interest)

I'm currently enrolled in a theory of interest class that covers the same material that's on exam 2/FM. At the instructors recommendation, I'm working through all of the problems in the book on my own ...
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1answer
444 views

Formula for APR with Odd Days

I need to programmatically calculate APR based on the following inputs: Principal Amount Number of payments (for example, 3 months loan is 3 if paying monthly, or 6 bi-weekly payments) Payment each ...
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1answer
708 views

brownian motion-proof of Martingale

Can anyone help me with the following problem? Let $W(t), t\geq 0$ be a Brownian motion with filtration:$F(t)$. Let $0\leq s\leq t$. 1- Show that $E\left [ W^{3}(t)\mid F(s) \right ...
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1answer
430 views

Markowitz portfolio optimization

Say that there are 5 assets with given mean values, standard deviations and correlations. Is it possible to find the expected return of a risk-seeking portfolio (maximum expected return) by using ...
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1answer
298 views

not getting the right proportion

I got this answer wrong. I thought it was 55% but it seems the answer is different. Please can you have a look at this and tell me where have I gone wrong and it should be. Thanks in advance. Q) ...
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1answer
69 views

Showing concavity of a function defined in terms of expectancy of another function

Suppose $ U : \mathbb{R} \to \mathbb{R} $ is concave, and that the random variable $ \epsilon $ has zero mean. Assuming that the function $ \phi : \mathbb{R} \to \mathbb{R} $, defined by $ ...
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2answers
13k views

Formula for calculating the total interest payable over the life of a loan

wondering if someone can help a non-mathematician out. I am looking for the formula for calculating the total interest payable over the life of a loan. Given that we know: ...
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2answers
274 views

Problem calculating percentage compound interest

I have two problems: 1. How can i calculate compound interest when i want to reinvest a percentage of the sum of my principal and interest periodically? To make it clearer, Usually i use this ...
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1answer
925 views

Rewriting Dividend Discount Model to derive residual income model

How can I rewrite this equation: $ \hspace{2in} V_0=\frac{E_1+B_0-B_1}{(1+r)^1} + \frac{E_2+B_1-B_2}{(1+r)^2} + \frac{E_3+B_2-B_3}{1+r)^3} + \dots $ into: $ ...
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1answer
33 views

Math Finance: Arbitragefree Pricing Q vs. P

I read that the Fundamental Theorem of Asset Pricing states, that a market is arbitrage-free if there exists a riskneutral equivalent martingale measure Q~P, under which the discounted asset price ...
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1answer
33 views

Recurrence On finance

A bank pays 6% interest at the end of each year on an account which initially starts with $2000. Find a recurrence relation for, the amount of money in the account at the end of year n if a) only ...
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2answers
54 views

Expected value of SinhX

A random variable X is distributed according to a normal distribution with mean u and variance d.How to evaluate the expected value of SinhX?Thanks
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1answer
43 views

Changing variables for a partial differential equation

If I have the following systems of PDE \begin{align} u_t+x^2u_{xx}-\dfrac{h_1(t)}{h_0(t)}e^{-(v-u)}-\dfrac{h_0'(t)}{h_0(t)}=0\\ v_t-\dfrac{h_0(t)}{h_1(t)}e^{-(u-v)}-\dfrac{h_1'(t)}{h_1(t)}=0, ...
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1answer
43 views

What is the minimum Premium to be asked for a risk X?

Suppose that an insurer has an exponential utility function $u(x) =-2e^{-2x}.$ What is the minimum premium $P^{-}$ to be asked for a risk X? I got some hint for this, but I could not understand ...
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1answer
60 views

Question about the risk analysis.

In the above one can see the detail of this question, I am beginner in this kind of mathematics. I will be very greatful if any one can help me to solve them.
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1answer
127 views

Calculating the value of Annuities

Q: Instead of investing $3000$ at the end of $5$ years, and $\$4000$ at the end of $10$ years, Steve wishes to make regular monthly payments that will amount to the same total after $10$ years. ...
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2answers
126 views

Compound interest problem

Find the present value and accumulated value after 10 years for an income stream with the rate of money flow $f(t) = 200 + 150t$ dollars per year and the rate of interest 12% compounded continously. ...
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1answer
82 views

Stochastic differential for general semimartingale

By using the canonical representation of a semimartingale in Eberlein, Glau and Papapantoleon: "$H = B + H^c + h(x) \ast (\mu − \nu) + (x − h(x)) \ast μ$ where $h = h(x)$ is a truncation ...
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1answer
840 views

How are Annuity problems solved?

I'm unsure how to solve the following problem: Angie wants to plan a trip to Hawaii with her husband on their 10th wedding anniversary in two years. She anticipates that the all-inclusive trip will ...
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1answer
253 views

Normal Distribution Quantiles and Value at Risk

I'm preparing an exam, Quantitative Methods for Financial Markets. My book is not really clear for what concerns the calculation of normal distribution quantiles that have to be used in VaR's formula. ...
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1answer
119 views

Variance Covariance Matrix, positive definiteness

Suppose we have a variance covariance matrix $\Sigma$. Under what conditions on the variance covariance matrix, $\Sigma$ is positive definite, that is $\forall w \neq 0, w^T \Sigma w>0$. In fact, ...
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1answer
76 views

simple interest rate to product of interest rates

Which simple interest rate over six years is closest to being equivalent to the following: an effective rate of discount of 3% for the first year, an effective rate of discount of 6% for the second ...
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1answer
23 views

Question About Notation of CRR

I am reading a book on financial theory and it has been a while since I took a notation heavy math course so could someone help me out here... Now with this equation how does the sum work? Do I do ...
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1answer
61 views

How does one calculate product pricing to cover processing fees from $\$5$ to $\$5,000$ while maintaining a profit?

Credit card processor charges, for each transaction, $2.9\% + \$0.30$. I need to find an amount that covers that cost, from $\$5$ to $\$5,000$, on a per item basis, all while maintaining a small ...
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1answer
70 views

Deferred Annuity not working

A simple financial math problem: Mack obtains $500\ 000$ repayable over $20$ years. If interest is compounded monthly at $9.25\%$ per annum, determine the monthly repayments if the repayment ...
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1answer
164 views

if you invest $ 500 at 6 % compounded annually,

Please help me with this problem. It needs to be done in the same format as below if you invest $500$ dollars at $6$ percent compounded annually, how many years to the nearest tenth would it take your ...
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1answer
128 views

american put option

For a perpetual american put option $v(s)$, satisfies the following problem: $$\frac12\sigma^2S^2\frac{\mathrm d^2V}{\mathrm dS^2}+(r-D)S\frac{\mathrm dV}{\mathrm dS} - rV = 0\quad\text{for ...
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1answer
1k views

Increasing and decreasing annuity

Going in circles..... Find an expression for the present value of an annuity-immediate where payments start at 1, increase by 1 each period up to a payment of $n$, and then decrease by 1 each period ...
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1answer
140 views

Continuous annuity calculation

This is a problem from Marcel Finan's Exam FM/2 course. It is not homework but I am studying for the FM exam and trying to get through this. You are given $\frac{d}{dt}\bar{s}_t$ = $(1.02)^{2t}$. ...
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2answers
169 views

Calculating the same exchange rate to make an investor indifferent

If we consider an American investor in 2009 with 160 million Dollars to place in a bank deposit in either America or the UK. The (1 yr) interest rate on bank deposits is 6 percent in the UK and 1 ...
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1answer
406 views

Determine the effective annual interest rate on the loan

A borrower owes \$5000 today and has promised to pay \$1900 at the end of the next three years to repay the loan. Determine the effective annual interest rate on the loan. What is the outstanding ...