What function is an example of exponential growth

Exponential growth functions are the functions that normally take the form 
y=ab^x
where:
a=initial value
b=growth rate
x=time
An example of situation that takes this form is the population growth of a particular group say and organism. 

x/7.50 = 15

x= 7.50 / 15 divide

x = 2

step-by-step explanation:

When rates are expressed as a quantity of 1, such as 2 feet per second or 5 miles per hour, they are called unit rates. if you have a multiple-unit rate such as 120 students for every 3 buses, and want to find the single-unit rate, write a ratio equal to the multiple-unit rate with 1 as the second term.