26)Suppose you deposit $ 2000 in a savings account that pays interest at an annual rate of 4%. If no money is added or withdrawn from the account, answer the following questions.
a. how much will be in the account after 3 years
b. how much will be in the account after 18 years
c. how many years will it take for the account to contain $2500
d. how many years to contain $3000
28) write an exponential function to model the situation. find the amount
a polulation of 1,860,000 decreases 1.5% each year for 12 years
a) is this
A = 2000(1.04)3 ≈ $2249.73 ......where A is the amount after 3 years
b) is similar, Nataszaa....just substitute "18' for the exponent of "3"
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c) so we have
2500 = 2000(1.04)t .......we are trying to find "t"......
First, divide both sides by 2000
2500/2000 = (1.04)t .......simplify this on the left
5/4 = (1.04)t ........take the log of both sides
log(5/4) = log(1.04)t ........and by a property of logs, we can bring the "t" "out front"
log(5/4) = t log(1.04) .........divide both sides by log(1.04)
log(5/4)/log(1.04) = t = about 5.7 years
d) is similar.....just replace "2500" with "3000" and follow the same steps....
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28) P = 1,860,000(.984)12 .....where P is the population after 12 years.....
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And there you go, Nataszaa.....
26) Just use the compound int formula
FV=P(1+r)^n
where P=2000
n=number of years
r=0.04
a) is this
A = 2000(1.04)3 ≈ $2249.73 ......where A is the amount after 3 years
b) is similar, Nataszaa....just substitute "18' for the exponent of "3"
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c) so we have
2500 = 2000(1.04)t .......we are trying to find "t"......
First, divide both sides by 2000
2500/2000 = (1.04)t .......simplify this on the left
5/4 = (1.04)t ........take the log of both sides
log(5/4) = log(1.04)t ........and by a property of logs, we can bring the "t" "out front"
log(5/4) = t log(1.04) .........divide both sides by log(1.04)
log(5/4)/log(1.04) = t = about 5.7 years
d) is similar.....just replace "2500" with "3000" and follow the same steps....
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28) P = 1,860,000(.984)12 .....where P is the population after 12 years.....
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And there you go, Nataszaa.....