1. To find simple interest, you multiply the principal (in dollars), the interest rate (as a decimal), and the time in years. The equation 24.00 = 400 · 0.015 · 4 shows how to find the simple interest for a certain account after 4 years.
a. What is the interest rate (as a percent)?
A. 0.015%
B. 400%
C. 1.5%
D. 24.00%
b. How much is the simple interest?
A. $4
B. $1.50
C. $24.00
D. $400
c. What is the principal?
A. $4
B. $24.00
C. $400
D. $1.50
2. Suppose you deposited $100 in a savings account 4 years ago. The simple interest rate is 2.2%. The interest that you earned in those 4 years is $8.80.
Which of the following is/are true? Select all that apply.
A. r = 2.2%
B. p = 100
C. I = 4
D. t = 8.80
3. An account has a principal of $500 and a simple interest rate of 3.3%. Figure 1 below shows the simple interest earned and the new account balance for 1, 2, and 3 years. Complete the table in Figure 1 for the fourth year.
4. If the simple interest on $2,000 for 2 years is $320, then what is the interest rate?
5. Edward deposited $6,000 into a savings account 4 years ago. The simple interest rate is 3%.
a. How much money did Edward earn in interest?
b. What would be his new account balance?
6. Think About the Process You deposit $2,900 into a bank account with a simple interest rate of 10%.
a. How do you find your account balance after 5 years?
A. First use I = prt to find the simple interest earned after 5 years. Then add that to the rate.
B. First use I = prt to find the simple interest earned after 5 years. Then add that to the time.
C. First use I = prt to find the simple interest earned after 5 years. Then subtract that from the principal.
D. First use I = prt to find the simple interest earned after 5 years. Then add that to the principal.
b. What will your account balance be after 5 years?