Suppose he bought a RMB treasury bill, then a+a* 14%*3=4970, and the solution is a=3500.

So that year he bought 3500 yuan of treasury bills.

1, the sum of principal and interest is the sum of principal and interest.

2. For example, the principal 100, the principal 105, and the storage time is 6 months.

Then interest = 105- 100=5.

So the six-month interest rate =5/ 100=5%.

Then the annual interest rate =5%*2= 10%.

3. The formula of compound interest is to calculate the interest in the previous period, which is included in the repeated interest calculation of principal, that is, "interest generates interest" and "rolling interest". There are two main calculation methods: one is to calculate compound interest at one time; The other is the calculation of equal multiple payment of compound interest.

Its characteristic is that the sum of the principal and interest at the end of the previous period is taken as the principal of the next period, and the amount of the principal of each period is different when calculating. It is mainly used to calculate the final value of principal and interest of multiple equal investments and the value of multiple equal payments.

The annual interest rate refers to the deposit interest rate for one year. The so-called interest rate is the abbreviation of "interest rate", which refers to the ratio of interest amount to deposit principal or loan principal in a certain period of time. Usually divided into annual interest rate, monthly interest rate and daily interest rate. The annual interest rate is expressed as a percentage of the principal, the monthly interest rate as a percentage, and the daily interest rate as a percentage.

When the economic development is in the growth stage, the investment opportunities of banks increase, the demand in loanable funds increases and the interest rate rises; On the other hand, when the economic development is sluggish and the society is in a depression period, the willingness of banks to invest is reduced, and the demand for loanable funds is naturally reduced, and the market interest rate is generally low.

1. national debt refers to a kind of government bond issued by the state financial organ to make up for the imbalance of the national treasury revenue and expenditure.

2. Treasury bills were invented by British economist and writer Walter Bazott in 1877, and were first issued in Britain. Because the debtor of the national debt is the country, its repayment guarantee is the national fiscal revenue, and there is almost no risk of credit default, so it is the least risky credit tool in the financial market.

3. The shortest term of China's national debt is one year, while there are many kinds of national debt in western countries, which can be generally divided into four types: three months, six months, nine months and 1 year, and the starting point of denomination varies from country to country.

Features:

Treasury bill rate is closely related to commercial bills and certificates of deposit. Treasury bond futures can provide hedging for other certificates when the income fluctuates. Strong liquidity. National debt has a broad secondary market, easy to change hands, can be realized at any time, and has a high reputation.