Answer: there would be 9 chipmunks after 5 years.
Explanation:
An initial population of 7 chipmunks in Mary's yard increases by 6% each year. It means that the population is increasing in an exponential rate.
The function that models the situation is expressed as
f(x) = ab^x
Where
a represents the initial population of chipmunks
b represent the rate of growth
x represent the number of years
From the information given,
a = 7
b = 1 + 6% = 1 + 6/100 = 1.06
x = 5 years
After 5 years,
f(5) = 7 × 1.06^5
f(5) = 9