# Interest – Part 1 Simple Interest When we talk about investment or borrowing money, we need to understand interest.

For most of us, we had learned how to calculate interest when we were at school, but we might not put much attention to it because we were too young to understand its implication. We only learn the mathematical aspect of it without understanding how important it will be when we grow up and start saving, investing or borrowing.

Today we will learn about SIMPLE INTEREST. Interest is how much you pay for the use of money. If you borrow money, then you pay interest. If you lend or invest money, then you earn interest.

Example 1: If you invest Rp 1,000,000 and the interest rate is 12% a year. How much interest will you get in 3 year?

You will get an interest of = Rp 1,000,000 x 12% x 3 = Rp 360,000

The amount of money you will have after three years is

Rp 1,000,000+ Rp 360,000 = Rp 1,360,000.

Example 2: If you borrow Rp 5,000,000 and the interest rate is 10% a year. How much you will have to pay if you borrow for 3 years?

You will have to pay back  = Rp 5,000,000 + ( Rp 5,000,000 x 10% x 3)

= Rp 5,000,000 + Rp 1,500,000

= Rp 6,500,000

Tomorrow, we will learn about COMPOUND INTEREST.

Learn and Grow

Inge Santoso, B Com, CFP®