Exponential function + time - math problems

Number of problems found: 51

Suppose 2
Suppose that the half-life of a substance is 250 years. If there were initially 100 g of the substance, a. Give an exponential model for the situation b. How much will remain after 500 years?
Car value
The car loses value 15% every year. Determine a time (in years) when the price will be halved.
Suppose 3
Suppose that a couple invested Php 50 000 in an account when their child was born, to prepare for the child's college education. If the average interest rate is 4.4% compounded annually, a, Give an exponential model for the situation b, Will the money be
Exponential warm
Suppose that a body with temperature T1 is placed in surroundings with temperature T0 different from that of T1. The body will either cool or warm to temperature T(t) after time t, in minutes, where T(t)=T0 + (T1-T0)e^(-kt) . If jello salad with 30 degree
How much 2
How much money would you need to deposit today at 5% annual interest compounded monthly to have $2000 in the account after 9 years?
If you 3
If you deposit $4500 at 5% annual interest compound quarterly, how much money will be in the account after 10 years?
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?
Population
What is the population of the city with 3% annual growth, if in 10 years the city will have 60,000 residents?
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.
Two years
Roy deposited 50,000.00 into his account paying 4% annual interest compounded semi annually. How much is the interest after 2 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?
Exponential decay
A tank contains 55 liters of water. Water is flowing out at the rate of 7% per minute. How long does it take to drain the tank?
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?
Deposit
If you deposit 719 euros the beginning of each year, how much money we have at 1.3% (compound) interest after 9 years?
Compound interest 4
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?
Doubling
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?
If you 4
If you deposit $2500 in an account paying 11% annual interest compounded quarterly, how long until there is the $4500 in the account?