Five-Minute Check (over Lesson 7–7)
Main Idea and Vocabulary
Example 1:Find Interest Earned
Example 2:Find Interest Earned
Example 3: Find Interest Paid on a Loan
Example 4: Find Total Paid on a Credit Card
• principal
• simple interest
• Solve problems involving simple interest.
Find Interest Earned
SAVINGS Brandon found a bank offering a certificate of deposit that pays 4% simple interest. He has $1,500 to invest. How much interest will he earn in 3 years?
I = prt Formula for simple interest
I = 1,500 ● 0.04 ● 3 Replace p with $1,500, r with 0.04, and t with 3.
I = 180 Simplify.Answer: Brandon will earn $180 in interest in 3 years.
1. A
2. B
3. C
4. D
A. $60
B. $300
C. $450
D. $6000
SAVINGS Cheryl opens a savings account that pays 5% simple interest. She deposits $600. How much interest will she earn in 2 years?
Find Interest Earned
SAVINGS Brandon found a bank offering a certificate of deposit that pays 4% simple interest. He has $1,500 to invest. How much interest will he earn in 30 months?
Answer: Brandon will earn $150 in interest in 30 months.
I = prt Formula for simple interest
I = 1,500 ● 0.04 ● 2.5 p = $1,500, r = 0.04, t = 2.5
I = 150 Simplify.
2.5 years Write the time as years.
1. A
2. B
3. C
4. D
A. $28
B. $280
C. $2,800
D. $3,360
SAVINGS Micah opens a savings account that pays 4% simple interest. He deposits $2,000. How much interest will he earn in 42 months?
Find Interest Paid on a Loan
LOANS Laura borrowed $2,000 from her credit union to buy a computer. The interest rate is 9% per year. How much interest will she pay if it takes 8 months to repay the loan?
I = prt Formula for simple interest
Answer: Laura will pay $120 in interest in 8 months.
I = 120 Simplify.
Replace p with $2,000, r with
0.09, and t with
I = 2,000 ● 0.09 ●
1. A
2. B
3. C
4. D
A. $225
B. $1,500
C. $2,250
D. $25,000
LOANS Juan borrowed $7,500 from the bank to purchase a used car. The interest rate is 15% per year. How much interest will he pay if it takes 2 years to repay the loan?
CREDIT CARDS Alma charged a $30 handbag on her credit card with an interest rate of 8%. How much money will she owe if she has no other charges on the card, and she does not pay off the balance at the end of the month?
Answer: So, the total amount owed would be $30 + $0.20 or $30.20.
Find Total Paid on a Credit Card
I = prt Formula for simple interest
I = 0.20 Simplify.
Replace p with $30, r with 0.08,
and t with
I = 30 ● 0.08 ●
1. A
2. B
3. C
4. D
A. $45
B. $60.45
C. $64.05
D. $65.95
CREDIT CARDS Curtis charged a $60 power tool on his credit card with an interest rate of 9%. How much money will he owe if he has no other charges on the card and he does not pay off the balance at the end of the month?
Five-Minute Check (over Lesson 7–7)
Image Bank
Math Tools
Percent of a Number
Percent of Change
1. A
2. B
3. C
4. D
(over Lesson 7-7)
$120 jacket; 30% discount
$12,300 car; 5% sales tax
Find the total cost or sale price to the nearest cent.
$12 book; 8.5% sales tax
Find the percent of discount to the nearest percent. regular-priced meal: $32.50; employee meal: $13
A shirt at the store is advertised “Buy 2, Get 1 Free.” If the original price of the shirt is $12.99 and you take advantage of the special offer, what is the price you would pay per shirt, and what percent is the discount from the original price?
A hotel room costs $155 per night. What is the total cost with a 30% discount and 5.5% sales tax?
1. A
2. B
3. C
4. D
(over Lesson 7-7)
A. $36
B. $84
C. $150
D. $156
Find the total cost or sale price to the nearest cent. $120 jacket; 30% discount
1. A
2. B
3. C
4. D
(over Lesson 7-7)
A. $12,915
B. $12,685
C. $11,915
D. $11,685
Find the total cost or sale price to the nearest cent. $12,300 car; 5% sales tax
1. A
2. B
3. C
4. D
(over Lesson 7-7)
A. $10.98
B. $11.98
C. $12.02
D. $13.02
Find the total cost or sale price to the nearest cent. $12 book; 8.5% sales tax
1. A
2. B
3. C
4. D
(over Lesson 7-7)
A. 85%
B. 60%
C. 40%
D. 15%
Find the percent of discount to the nearest percent. regular-priced meal: $32.50; employee meal: $13
1. A
2. B
3. C
4. D
(over Lesson 7-7)
A. $6.49 per shirt; 50% discount
B. $6.94 per shirt; 50% discount
C. $8.66 per shirt; 66% discount
D. $8.66 per shirt; 33% discount
A shirt at the store is advertised “Buy 2, Get 1 Free.” If the original price of the shirt is $12.99 and you take advantage of the special offer, what is the price you would pay per shirt, and what percent is the discount from the original price?
1. A
2. B
3. C
4. D
(over Lesson 7-7)
A. $46.50
B. $108.50
C. $114.47
D. $190.42
A hotel room costs $155 per night. What is the total cost with a 30% discount and 5.5% sales tax?