Exponential function + percentages - math problems

Number of problems found: 37

  • Decibel
    tv By what percentage does the sound intensity increase if the sound intensity level increases by 1 dB?
  • Slow saving in banks
    penize How long will it take to save € 9,000 by depositing € 200 at the beginning of each year at 2% interest?
  • Savings
    500eur The depositor regularly wants to invest the same amount of money in the financial institution at the beginning of the year and wants to save 10,000 euros at the end of the tenth year. What amount should he deposit if the annual interest rate for the annua
  • Car down
    car Sarah buys a car costing $12,500. It depreciates value by 8% in the first year, 10% in the second year, and 5% in the third year. Calculate the value of a car after the third year.
  • Annual pension
    penize Calculate the amount of money generating an annual pension of EUR 1000, payable at the end of the year and for a period of 10 years, shall be inserted into the bank to account with an annual interest rate of 2%
  • Precious metals
    gold In 2006-2009, the value of precious metals changed rapidly. The data in the following table represent the total rate of return (in percentage) for platinum, gold, an silver from 2006 through 2009: Year Platinum Gold Silver 2009 62.7 25.0 56.8 2008 -41.3 4
  • The crime
    crime The crime rate of a certain city is increasing by exactly 7% each year. If there were 600 crimes in the year 1990 and the crime rate remains constant each year, determine the approximate number of crimes in the year 2025.
  • Account operations
    penize My savings of php 90,000 in a bank earns 6% interest in a year. If i will deposit additional php 10,000 at the end of 6 months, how much money will be left if i withdraw php 25,000 after a year?
  • Investment
    penize 1000$ is invested at 10% compound interest. What factor is the capital multiplied by each year? How much will be there after n=12 years?
  • Repay, interest, loan
    repay Ramchacha takes a loan amount of 240000 from a bank for constructing a house at the rate of simple interest of 12% per annum. After 1 yr. of taking the loan he rents the house at the rate of 5200 per month. Determine the number of years he would take to r
  • BTC bubble
    btc One of the world's experts in bubbles -- Prof. Robert Shiller, a Yale economist -- said Bitcoin "was an amazing example of a bubble" back in 2014. If you exchange fiat US dollar $100 to BTC in 2010, now in 2017 have value of 72.9 millions dollars. Find an
  • Compound interest
    bank 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?
  • Combined interest
    bank2 Combined interest: Carol has deposited CZK 100,000 in the bank with an annual interest rate of 1.5%. The money was put into the account 5.5.2016 and withdraw them all before Christmas 20.12.2016. How much money did she withdraw?
  • The deposit
    money 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.
  • Car value
    car_old The car loses value 15% every year. Determine a time (in years) when its price will halve.
  • The city 2
    kingkong Today lives 298000 citizens in the city. How many citizens can we expect in 8 years if their annual increase is 2.4%?
  • The city
    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?
  • Deposit 3
    interest_money After a year, Martin had on bank account € $b. What was the interest rate when the initial deposit was € $a?
  • Enterprise
    podniky_socik 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?
  • Simple interest
    bank 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?

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