Calculating Simple Interest with Different Time Units

The video tutorial explains how to calculate simple interest using the formula I = PRT, where I is interest, P is principal, R is rate, and T is time. It provides examples to demonstrate how to calculate interest, solve for different variables like principal, rate, and time using a triangle method. The tutorial includes practical examples such as Ian's investment, Surley's loan, Doug's investment, and Kim's loan, illustrating how to apply the formula in real-world scenarios.

What is the formula for calculating simple interest?

• Interest = Principal * Rate * Time

• Interest = Principal + Rate + Time

• Interest = Principal - Rate - Time

• Interest = Principal / (Rate * Time)

How do you convert a percentage rate to a decimal for the formula?

• Multiply by 100

• Divide by 100

• Add 100

• Subtract 100

What is the principal in the context of simple interest?

• The initial amount of money borrowed or invested

• The total amount of interest paid

• The rate of interest as a decimal

• The time period in years

How is the interest rate expressed in the simple interest formula?

• As a percentage

• As a decimal

• As a whole number

• As a fraction

What does the 'T' represent in the simple interest formula?

• Tax rate

• Time in years

• Transaction number

• Total amount

If Ian invests $4,000 at a 5.5% rate for 2 years, how much interest will he earn?

• $110

• $220

• $440

• $880

To solve for the principal in the simple interest formula, which is correct?

• Principal = Interest + Rate + Time

• Principal = Interest / Rate

• Principal = Interest / (Rate * Time)

• Principal = Interest * Rate * Time

What was the interest rate for Surley's loan if she paid $90 in interest on a $1,200 loan over 2 years?

• 3.75%

• 7.5%

• 6%

• 4.5%

Doug made an investment that earned $675 in interest over 3 years at a 4.5% rate. What was his original investment?

• $10,000

• $15,000

• $7,500

• $5,000

Kim took a $4,700 loan at a 7.5% rate and paid $1,575 in interest. How many years did it take to pay off her loan?

• 4 years

• 5 years

• 3 years

• 2 years