1. CHAPTER NINE
Simple Interest

2. Basics of Simple Interest
Section 9.1
Basics of Simple Interest

3. Simple Interest Formula
I = P∙R∙ T
EX: Find the interest on a loan of $14,680 for 6 months at 9% simple interest.

4. Maturity Value
… the amount that must be repaid when the loan is due.
M = P + I
EX: Find the maturity value of a loan of $25,000 at 9% simple interest for 8 months.

5. Finding the # of days… Use table on P 331 Find the number of days…
From July 7 to November 7.
From August 25 to January 20 of the following year.
From March 14 to September 9.

6. Find Exact and Ordinary Interest
If the time is given in DAYS…
For EXACT interest:
T = # of days in loan period
365
For ORDINARY interest:
360

7. Find the exact and ordinary interest for a 200 day loan of $19,500 at 9% simple interest. Then find the difference between the two interest amounts.
We will use Ordinary Interest unless specified otherwise!

8. Due Date of a Note Time is often given in Months
So the due date is after the given # of months have passed, but on the same day of the month.
Find the due date for a 6-month loan made on March 31.