The number of shoppers is an illustration of an exponential function.
The expression for the number of shoppers is: 
The given parameters are:
<em />
<em> -- the number of shoppers on the first day of business</em>
<em />
<em> --- the rate</em>
<em />
Because, the number of shoppers <em>increases each day</em>, the number of shopper on a certain day is:

Substitute 15% for r

Express percentage as decimal


Substitute 150 for a


Hence, the expression for the number of shoppers is: 
Read more about exponential functions at:
brainly.com/question/11487261