In the business sector we use mathematics to determine the profitability & attractiveness of a company from an investment point of view.  You look at things like earnings per share (EPS - net income of the company / # shares), profit margin (sales less direct cost of sales), dividend payout ratio (dividends / net income).  Although the math involved in these calculations is simple, the information is invaluable.

Other calculations used in business are more finance related and take into account the time value of money.  For instance, the present value of an annuity (a stream of future payments) is compared with the current cost alternative of that annuity to decide on a course of action.  The implicit interest rate used is of great importance in that calculation.  Einstein once said that compound interest is the most powerful force of all time.  Compound interest is relatively simple calculation whereby your principal grows at the rate of interest and the interest earned continues to grow at that rate also.  Taxation schemes of the wealthy rely on the power of compound interest & the lack of taxation on unrealized capital gains to earn wealthy tax-free.

The above description is not meant as a dissertation on business accounting or finance calculations but merely to introduce some business related ideas in English.  If I am on the wrong track of what you are looking for, please let me know. 

On a language learning site?

 Hi Carrie:

 One application of Math is in our Technology Study Group  which meets on Wednesday.

We discuss.

Otherwise, one could say that balancing a checkbook  is an application.

 Moreover,  as a person who has  been involved in Homeschooling,   Math knowledge is necessary to teach to the children in the home.

I use these methods to solve heat transfer problems and to design fins and heat exchangers. I don't know if it used in business sector. I think you need to study statistics and some topics like probability but I am not sure though. Before some years ago, I read a book about statistics but unfortunately, I don't remember the name of author now. I know how to utter his name, his name some thing like krisich or chrisish. There I read about many statistics theory and I think this is what you need. You may want to find something about applied mathmatics or applaied numarical theory. I am not expert in business sector so I may did some mistakes.

thanks for Comandante. but your answer is very difficult for me. I do not study physics. do you have some ideas about this question in business sector?