# Exponential function + percentages - 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?
• 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?
• Car value The car loses value 15% every year. Determine a time (in years) when the price will be halved. A radioactive material loses 10% of its mass each year. What proportion will be left there after n=6 years?
• 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?
• 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?
• Demographics The population grew in the city in 10 years from 30000 to 34000. What is the average annual percentage increase of population?
• 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?
• Decibel By what percentage does the sound intensity increase if the sound intensity level increases by 1 dB?
• 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?
• 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.
• 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?
• 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%
• Shuyen Shuyen wanted to save some money. She deposited Php.300 in a bank which pays 0.5% interest per annum. After nine months, she needed the money to buy some gifts. How much will she be able to get if he withdraws all her money from the bank?
• 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?
• 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.
• 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?

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