Exercise 30 Page 270

Use the simple interest formula to find the interest.

$ 2550

Practice makes perfect

Let's start by looking at the first row of the given table!

Principal	Annual Interest Rate	Time	Simple Interest
$12 000	4.25 %	5 years

We want to calculate the simple interest. We can do so using the simple interest formula that tells us that simple interest I is the product of the principal P, annual interest rate (in decimal form) r, and time (in years) t. I=Prt Here, the principal P is 12 000 dollars and the time t is 5 years. We also know that the interest rate of 4.25 % can be written as 0.0425. Now, we can substitute these values into the formula.

I=Prt

SubstituteValues

Substitute values

I= 12 000( 0.0425)( 5)

Multiply

I=2550

The simple interest is $ 2550. We can use this information to complete the table.