Exponential function - math word problems

Number of problems found: 62

  • Decibel
    tv_1 By what percentage does the sound intensity increase if the sound intensity level increases by 1 dB?
  • Slow saving in banks
    penize_5 How long will it take to save € 9,000 by depositing € 200 at the beginning of each year at 2% interest?
  • Compound interest 4
    exp_growth2 3600 dollars is placed in an account with an annual interest rate of 9%. How much will be in the account after 25 years, to the nearest cent?
  • The half life
    exp_growth2 The half-life of a radioactive isotope is the time it takes for a quantity of the isotope to be reduced to half its initial mass. Starting with 145 grams of a radioactive isotope, how much will be left after 3 half-lives?
  • Savings
    bankovka 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
  • Mortage hypo loan
    hypo The Jonáš family decided to buy an older apartment, which cost EUR 30,000. They found EUR 17,000 and took the loan with the bank for the remaining amount. What interest did they receive if they repay this amount for 15 years at EUR 120 per month?
  • Car down
    car_1 Sarah buys a car costing $12,500. It depreciates in value by 8% in the first year, 10% the second year and 5% in the third year. Calculate the value of a car after the third year.
  • Microorganisms
    microorganisms The first generation of micro-organisms has a population of 13500 members. Each next generation is 11/10 times the previous one. Find out how many generations will reach at least three times members of the first generation.
  • Profit growth
    growth The profit of a company increased by 25% during the year 1992, increased by 40% during the year 1993, decreased by 20% in the year 1994 and increased by 10% during the year 1995. Find the average growth in the profit level over the four years periods?
  • Drilling machine
    heavy-drilling-machine-500x500 A manufacturing firm purchased a heavy duty drilling machine. They were given two payment options: Option 1: Make a payment of $46,000 immediately to settle the invoice for the machine. Option 2: Make a payment of $21,500 immediately and the balance of $2
  • 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.
  • Compound interest 3
    exp_growth2 After 8 years, what is the total amount of a compound interest investment of $25,000 at 3% interest, compounded quarterly? (interest is now dream - in the year 2019)
  • Account operations
    penize_49 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?
  • A loan
    exp_growth A loan in the amount of $944 is charged simple interest at an annual rate of 8.1%. How much money is owed 14 months after the loan was made?
  • Radioactive material
    radium A radioactive material loses 10% of its mass each year. What proportion will be left there after n=6 years?
  • Doubling
    exp_5 The message is spreading that each day has doubled the number of people who know about it. All know message for 20 days. How long known it eighth people?
  • The deposit
    money_13 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.
  • Saving 9
    penize_40 An amount if $ 2000 is invested at an interest of 5% per month. if $ 200 is added at the beginning of each successive month but no withdrawals. Give an expression for the value accumulated after n months. After how many months will the amount have accumul
  • Annual pension
    penize_49 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_3 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

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