Question

i need help

Answer 1

A certain forest covers an area of 1900km^2 . Suppose that each year this area decreases by 9% . What will the area be after 13 years?
Use the calculator provided and round your answer to the nearest square kilometer

Answer 2

use geometric sequence
\[\huge a_n = a_1 r^{n-1}\]
a_n is what you're looking for
a1 is 1,900
r would be 0.09
n would be 13

does that help?

Answer 3

decrease by 9% or 0.09 means multiply by 0.91 for each year
for example, if you start with 100, after 1 year, you get 91 (0.91*100)

here you want
1900* 0.91^13
where 13 is the power (# of years)