# Exponential function - math word problems

#### Number of problems found: 80

• 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%
• Annual interest
A loan of 10 000 euro is to be repaid in annual payments over 10 years. Assuming a fixed 10% annual interest rate compounded annually, calculate: (a) the amount of each annual repayment (b) the total interest paid.
• Compound interest 3
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)
• Annual growth
The population has grown from 25,000 to 33,600 in 10 years. Calculate what was the average annual population growth in%?
• Common ratio
If 200 units of a commodity are consumed in a first year, and if the annual rate of increase in consumption is 5% (a) what amount is consumed in the 8th year; (b) in the first 15 years?
• 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?
• 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.
• Bank
Paul put 10000 in the bank for 6 years. Calculate how much you will have in the bank if he not pick earned interest or change deposit conditions. The annual interest rate is 3.5%, and the tax on interest is 10%.
• 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?
• Future value
Suppose you invested \$1000 per quarter over a 15 years period. If money earns an anual rate of 6.5% compounded quarterly, how much would be available at the end of the time period? How much is the interest earn?
• RC time constant
You introduced 1 Coulomb worth of electrons into the inner volume of a dielectric material with ϵr=6. 30 minutes later, you found that only 36.79% of the electrons were in the inner volume. Determine the conductivity σ of the dielectric material.
• 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?
• Combined interest
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?
• A loan
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?
• The half life
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?
• Reducing balance method
A company buys an item having a useful life of 10 years for 1,000,000. If the company depreciates the item by the reducing balance method, a. Determine the depreciation for the first year. b. Estimate the depreciation for the second and third years. c. Wh

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