y=a(0.2)^t/8. Can someone help me solve this and I need to know if it is growth or decay

Question

I have been having trouble with this question and the topic about this the Natural Base Exponential Function

Answer 1

See my Comment. At the end of each time interval of duration t/8, the value of y is 0.2 times what it was at the start of the interval.  This is decay. To get growth, you need a number > 1 for the argument of the exponential function:  Example:

 

y(t) = A(1.5)^t

 

At the end of each time interval of duration t, the value of y is 1.5 times what it was at the start of the interval. This is growth.