Download Targeted review 4 Growth and Decay

Targeted Review 4: Growth and Decay
Name__________________
Convert each percent to a decimal.
75%
8%
100%
250%
y = final amount
r
A = P (1 + ) nt
n
A = final amount
a = stating amount
P = Principal
r = rate as a decimal
r = rate as a decimal
y = a (1 + r )t
t = time
y = a (1 − r )t
.01%
2.5%
n = # of times interest is paid per year
t = time
There are 5 bacteria in a petri dish. If the bacteria reproduce at a rate of 200% per hour, how
many bacteria will be in the petri dish in 16 hours?
a=
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Bob puts $5,000 into a bank account that pays 6% interest compounded monthly. What will
Bob’s bank balance be in 20 years?
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A hunter brings 20 rabbits to an island where they have no predators. The rabbits reproduce at a
rate of 350% a year. How long will it take for there to be 10,000 rabbits on the island?
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Siegfried’s sausage factory sold 20,000 sausages in 2010. If his sales decrease by 8% each year
how many sausages will he be selling in 2025?
a=
r=
t=
y = final amount
r
A = P (1 + ) nt
n
A = final amount
a = stating amount
P = Principal
r = rate as a decimal
r = rate as a decimal
y = a (1 + r )t
t = time
y = a (1 − r )t
n = # of times interest is paid per year
t = time
John had a 500 pound block of cheese. If 10% were eaten each week, how much cheese would
be left after 1 year? (1 year = 52 weeks)
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Amanda buys a $10,000 CD that pays 3% interest compounded quarterly. What will Amanda’s
CD be worth when it matures in 10 years?
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The math club has 10 members. Each year it grows by 3.14% . How many members will the
math club have in 50 years?
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The joisting club has 100 members. Each year it shrinks by 7 % . How many members will the
joisting club have in 20 years?
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r=
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