Answer: the expected population in 1999 is 1412
Explanation:
The population is decreasing in geometric progression. This is true because there is a common ratio between consecutive years.
Common ratio = 24500/35000 = 17150/24500 = 0.7
The formula for determining the nth term of a geometric progression is expressed as
Tn = ar^(n - 1)
Where
a represents the first term of the sequence.
r represents the common ratio.
n represents the number of terms.
From the information given,
a = 35000
r = 0.7
n = 10
The 9th term, T9 is
T9 = 35000 × 0.7^(10 - 1)
T9 = 35000 × 0.7^9
T9 = 1412