Precalculus
posted by jh
NEED HELP ASAP PLEASE!!
A savings account starts with $600 and pays 5% interest per year, compounded four times per year.
a) A function that models the amount in dollars in the bank account after m years is A(m)=____________?
b) How much will be in the savings account after 3 years? $______?
c) The amount in the account will exceed $1400 after ________ years.

Reiny
amount = 600(1 + .05/4)^(4m)
b) A = 600(1.0125)^12 = ...
c) set A = 1400
1400 = 600(1.0125)^n, remember n is quarter years.
2.33333 = (1.0125)^n
do you know how to do logs? If so, ..
n = log 2.33333/log 1.0125 = 68.2 quarter years or about 17 years.
notice 17 years > n= 68
amount = 600(1.0125)^68 = $1396.41
so you will need about 68 and 1/4 years.
Respond to this Question
Similar Questions

Math
If 3000 dollars is invested in a bank account at an interest rate of 6 per cent per year, find the amount in the bank after 12 years if interest is compounded annually Find the amount in the bank after 12 years if interest is compounded … 
Calculus :)
If 8000 dollars is invested in a bank account at an interest rate of 10 per cent per year, find the amount in the bank after 11 years if interest is compounded annually ____ Find the amount in the bank after 11 years if interest is … 
Alg2
Help....Help... Suppose you deposit a principal amount of p dollars in a bank account that pays compound interest. If the annual interest rate r (expressed as a decimal) and the bank makes interest payments n times every year, the … 
Alg 2
Suppose you deposit a principal amount of p dollars in a bank account that pays compound interest. If the annual interest rate r (expressed as a decimal) and the bank makes interest payments n times every year, the amount of money … 
math
Suppose $5000 is deposited in a bank account that compounds interest four times per year. The bank account contains $9900 after 13 years. What is the annual interest rate for this bank account? 
math
if you invest 500 dollars in a savings account that pays 8% interest per year, compounded quarterly, how much will you have in the account at the end of 11.6 years? 
Compound interest
Hello My teacher skipped over this and I have no clue how to do this or the equations. Help would be wonderful thank you If 6000 dollars is invested in a bank account at an interest rate of 10 per cent per year, find the amount in … 
differential equation
If P(t) is the amount of dollars in a savings bank account that pays a yearly interest rate of r% compounded continuously ,then dP/dt=(r/100)(P) , t in years . Assume the interest is 5% annually ,P(0)=$1000 ,and no monies are withdrawn … 
Calculus Please help!
If 7000 dollars is invested in a bank account at an interest rate of 7 per cent per year. A) Find the amount in the bank after 6 years if interest is compounded annually? 
Algebra ASAP
Suppose that $17,000 is invested in a savings account paying 5.1% interest per year. (a) Write the formula for the amount A in the account after t years if interest is compounded monthly. A(t) = (b) Find the amount in the account after …