1. OBJECTIVE: How do we find
simple interest?
Do Now
Fill in a Venn diagram with the following information:
28 students play soccer
35 students play basketball
12 students play both
How many students play at least one sport?
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2. Anticipatory Set
Explain, in a complete sentence, your understanding of
interest when dealing with bank accounts.
Simple Interest Formula: I = prt
Where I = interest
p = principal
r = interest rate as a decimal
t = time in years
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3. 1
Find the simple interest if you
deposit $1,200 at an interest rate of
5.5% for 2 years.
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4. 2
Find the simple interest if you borrow
$1,000 at an interest rate of 9.75%
for 4 years.
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5. 3
Find the simple interest if you borrow
$2,500 at an interest rate of 8% for 15
years.
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6. 4
Find the simple interest if you deposit
$1250 at an interest rate of 3.5% for 6
months. (HINT: Look back at the
formula written in your notes)
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7. 5
Find the simple interest if you borrow
$7500 at an interest rate of 5.5% for 9
months. (HINT: Look back at the
formula written in your notes)
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8. 6
4 years ago I deposited $500 into a savings
account, but I forgot the interest rate. If
the simple interest was $140, what is the
interest rate?
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9. Before You Leave
Compound Interest
Mortgage Payments
P[i(1 + i)]n
M=
[(1 + i)n - 1]
P = Principal
i = rate divided by 12
n = number of months
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