Doubts

Exercise 3 - In-class Topic 8

Exercise 3 - In-class Topic 8

by Alois Jari Thomas Neff -
Number of replies: 1
Dear Julio,

I have a question about exercise 3 of today's lesson:

Specifically, the first problem, "The company pays off the entire loan balance plus interest in two years." I don't really understand your calculation.

Shouldn't we calculate the interest payment in two years by calculating: 250*0.08*1.08 + 250*0.08*1.08^2, which would give ~44.9? Instead, we calculate 250×(1.08)^2 - 250 (which is the same as 250*0.08 + 250*0.08*1.08?), which is 41.6.

Could you maybe briefly explain the calculation?

Best, Alois
In reply to Alois Jari Thomas Neff

Re: Exercise 3 - In-class Topic 8

by Julio Crego -

Dear Alois, 

We start with a debt of 250

At the end of the year, we owe the same debt plus interest (250 + 0.08*250 = 1.08*250)

At the beginning of the second year, we owe 1.08*250

At the end of the second year, we need to pay interest on that debt: hence, the total debt payment is 250*1.08^2

If 250 is the principal, the remaining amount has to be interest.