Percentages + exponential function - math problems

Number of problems found: 33

Interest
What is the annual interest rate on your account if we put 32790 and after 176 days received 33939.2?
Car value
The car loses value 15% every year. Determine a time (in years) when the price will be halved.
Radioactive material
A radioactive material loses 10% of its mass each year. What proportion will be left there after n=6 years?
Demographics
The population grew in the city in 10 years from 30000 to 34000. What is the average annual percentage increase of population?
Decibel
By what percentage does the sound intensity increase if the sound intensity level increases by 1 dB?
Investment
1000$ is invested at 10% compound interest. What factor is the capital multiplied by each year? How much will be there after n=12 years?
Deposit 3
After a year had Martin on bank account € 2028. What was the interest rate when the initial deposit was € 1879?
Deposit
If you deposit 719 euros the beginning of each year, how much money we have at 1.3% (compound) interest after 9 years?
Population
The town has 65,000 inhabitants. 40 years ago, there were 157,000. How many people will live in a city in 10 years if the population's average rate is as in previous years?
Slow saving in banks
How long will it take to save € 9,000 by depositing € 200 at the beginning of each year at 2% interest?
The city
At the end of 2010 the city had 248000 residents. The population increased by 2.5% each year. What is the population at the end of 2013?
Loan 4
Mr santos borrowed Php.18,000 at 1.5% interest for one year. What was the total amount he paid for the end of the 1-year term?
Annual pension
Calculate the amount of money generating an annual pension of EUR 1000, payable at the end of the year and for a period of 10 years, shall be inserted into the bank to account with an annual interest rate of 2%
Crystal
The crystal grows every month 1.2 permille of its mass. For how many months to grow a crystal from weight 177 g to 384 g?
The crime
The crime rate of a certain city is increasing by exactly 7% each year. If there were 600 crimes in the year 1990 and the crime rate remains constant each year, determine the approximate number of crimes in the year 2025.
Enterprise
The value of annual production enterprise is 7.1 million USD. The average annual growth rate is 1.5%. What will be value of production at the end of the fifth year?
The deposit
Deposit has been placed for one year at an annual rate of 4.5%. After the added interst amount rose to € 2,612.5. Determine initial deposit.
Account operations
My savings of php 90,000 in a bank earns 6% interest in a year. If i will deposit additional php 10,000 at the end of 6 months, how much money will be left if i withdraw php 25,000 after a year?
Simple interest
Peter put into bank 853 euros deposit. After 7 years on account overall was 984 euro. What was the interest rate if bank add simple interest?
Compound interest
Compound interest: Clara deposited CZK 100,000 in the bank with an annual interest rate of 1.5%. Both money and interest remain deposited in the bank. How many CZK will be in the bank after 3 years?