Compound Interest is a clear example of Exponential Growth. Not only Exponential Growth though, it can also be used as Exponential Decay. Compound interest is the addition of interest to the principal amount of a loan or deposit, or in simpler words, interest on interest. Compound interest at a constant interest rate adds exponential growth. An example of Exponential Growth would be if my friend borrowed 5$ for snacks from the gas station from me every Tuesday in January and February, but he has to pay me at the end of the week. At the end of the months he'd have to pay me 40$. The equation for that would be y= 5(4)^2. An example of Exponential Decay would be if I loaned 50$ a month from the bank and hI did every month. At the end of 1 years I’d have 600 to pay back to the bank. The equation for that would be y= 600(.05)^2.