1. Objective - To solve problems involving simple interest.
If someone borrows money, what factors influence
how much is paid back?
Principal -
How much was borrowed.
Time -
How long it was borrowed for.
(in years)
Rate -
What interest was charged.
(annual % rate)
Amount to Payback =
Principal +
Interest
Interest =
Principal
Rate
Time

2. Joe borrows $200 from the bank at 6% simple
interest for 3 years. What interest does he owe,
and what is his total balance (amount to payback)?
Interest
Balance
Balance = P + I
Balance =
200 + 36
Balance = 236
Balance = $236

3. Juan invests $5000 in bonds for 6 months at an
annual interest rate of 7%. How much interest
did he earn, and what is the balance in his account?
Interest
Balance
Balance = P + I
Balance =
5000 +
175
Balance = 5175
Balance = $5175

4. Find the simple interest and the balance.+ I
Balance = P + I
Balance =
2000 + 60
Balance =
15,000 +
406.25
Balance = $2060
Balance = $15,406.25

5. Find the annual simple interest rate.

6. Find the annual simple interest rate.

7. Find the principal amount invested.