1. Do Now 4/11/11 Take out HW from last night. Copy HW in your planner.
Practice worksheet 7.6 odds
Copy HW in your planner.
Text p. 365, #8-16 evens and #15
Quiz sections Wednesday
Chapter 7 Test Friday
Be ready to copy POTW#3.

2. A shoe store in NJ has a sale on sneakers for 15% off
A shoe store in NJ has a sale on sneakers for 15% off. If the original price is$75 what is the total cost of the sneakers with tax?
Sale price =
Original price
Discount – = 75 –
(15% · 75) = 75 –
11.25 =
$63.75
Total Price =
Purchase Price
Sales Tax +
$63.75 +
(63.75 x 7%)
$63.75 +
4.46
$68.21

3. Homework Practice worksheet 7.6 odds
13) $83.64
15) $36.15
17) $19.38
19) $27.04
21) $57.40
1) $11.25
3) $273
5) $49.40
7) $30.60
9) $29.26
11) $86.51

4. Objective
SWBAT calculate interest earned and account balances

5. Section 7.7 “Simple and Compound Interest”
SIMPLE INTEREST-
Is the product of the principal, the annual interest rate, and the time in years.
Principal – the amount borrowed, loaned, or in savings.
Annual interest rate – the percent of the principal you would earn (or pay) as interest in ONE year.
Time in years – when time is less than a year, write time as a fraction of the year.

6. Writing Time in Years…
Time in years – when time is less than a year, write time as a fraction of the year.
Write the months as a fraction of a year.
3 months
7 months
10 months

7. Simple Interest
You have $1,000 in a savings account in a local bank. The annual interest rate is 3%. How much interest will the bank pay you in a month?
Principal = $1000
Interest rate = 3% or 0.03
Time = one month or 1/12

8. Simple Interest
You borrowed $18,000 for a new car. The annual interest rate is 12%. What is the interest you will have to pay in two years to borrow this money?
Principal = $18,000
Interest rate = 12% or 0.12
Time = two years or 2

9. Account Balance
When an account earns interest it is added to the money in the account. The BALANCE (A) of an account that earns simple annual interest is the sum of the principal (P) and the interest (Prt).
Balance

10. Finding an Interest Rate
Suppose you save $1400 in a savings account that earns simple annual interest. After 9 months, the balance in your account is $ Find the annual interest rate.
Principal = $1400
Balance = $1421
Time = 9 months
The interest
rate is 2%

11. This makes more “cents”…
COMPOUND INTEREST-
Is interest that is earned on BOTH the principal and any interest that has been earned previously.
Account balance– the amount of money in an account.
Principal – the amount borrowed, loaned, or in savings.
Annual interest rate – the percent of the principal you would earn (or pay) as interest in ONE year.
Time in years – when time is less than a year, write time as a fraction of the year.

12. This makes more “cents”…
You deposit $300 in the bank. This is your beginning balance. The annual interest rate is 6%. Each year the simple interest is computed and then added to your beginning balance. (this is compounded interest). If this pattern continues, how much will you have in the account at the end of 3 years?
Principal = $300
Interest rate = 6%
Time = 3 years
After 3 years you will have $357.30

13. Compound Interest
You deposit $1,500 in a savings account in a local bank. The annual interest rate is 2.4% compounded annually. Find the balance after 6 years?
Principal = $1500
Interest rate = 2.4% or 0.024
Time = 6

14. 24
Homework
Text p. 365, #8-26 evens

15. Word Problem
You deposit $300 in the bank. This is your beginning balance. The annual interest rate is 6%. Each year the simple interest is computed and then added to your beginning balance. If this pattern continues, how much will you have in the account at the end of 3 years?
After 3 years you will have $357.30
YEAR 1
YEAR 2
YEAR 3
Principal = $300
Principal = $318
Principal = $337.08
Interest rate = 6%
Interest rate = 6%
Interest rate = 6%
Time = one year
Time = one year
Time = one year