7 math: Lesson 2.8 Interest (I=prt)

Anna invested $2,500 at an annual rate of 5%.  How long will it take until Anna earns $1,125 in interest?

• 5 years
• 8 years
• 10 years
• 9 years

Javon has a credit card with a $1,583 balance. His interest rate is 8.8%. If he does not pay for 3 years, how much interest does he owe?

• $4,179
• $417.91
• $133,930
• $41,791

Calculate the interest.  I = PRT,
Principal = $10000,
Rate = 7%,
Time = 20 years

• 1400
• 1000
• 14000
• 14

Calculate the interest. I = PRT,

Principal = $1000,

Rate = 6%,

Time = 2 years

• $100

• $120

• $180

• 1200

The simple interest formula is I=Prt.  The P represents the principle.  The principle is ___________________.  

• the amount of money borrowed or deposited
• the percent interest for his year
• the amount taxed
• the amount the bank owes you for being a customer at their bank

The rate is given as a percent (%).  Before using it in the simple interest formula, you must first convert it to a______.

• fraction
• decimal
• ratio
• dollar amount

Allison was left an inheritance from her Aunt Lisa. She can not touch the money until she is 21 years old, Allison is now 12 years old and inherited $50,000 that was put into an account with 2% interest. How much interest will Allison have earned at her 21st birthday?

• $900
• $100,000
• $9,000

Starting money = $350.
Interest rate = 2.5%
TIme = 3 years.
How much interest?

• $7.50
• $26.25
• $87.5
• $262.50

Little Johnny scored a 15 on his last math test, but needs to score a 70 on the next one. What percent of increase does Johnny need to make?

• 85%

• 37%

• 55%

• 366.7%

You borrowed 43,800 at a SIMPLE interest rate of 4.8%. If you pay it back in 2 years, how much interest is paid pack?

• $464,280

• $85,848

• $4204.8

• $48,004.80