Answer:
1. a = 5400
2. r = 0.96
3. Percentage decrement = 65.4%
Step-by-step explanation:
Given
N = ar^t
Solving (a): Write down the value of a
a implies the first term
And from the question, we understand that the initial number of trees is 5400.
Hence,
a = 5400
Solving (b): Show that r = 0.96
Using
N = ar^t
When a = 5400, t = 1 i.e. the first year and N = 5184
Substitute these values in the above expression
5184 = 5400 * r¹
5184 = 5400 * r
5184 = 5400r
Solve for r
r = 5184/5400
r = 0.96
Solving (c): Show that the trees has decreased by over 65% in 2040
First, we need to calculate number of years (t) in 2040
t = 2040 - 2014
t = 26
Substitute 26 for t, 5400 for a and 0.96 for r in N = ar^t to get the number of trees left
N = 5400 * 0.96^26
N = 1868.29658019
N = 1868 (approximated)
Next, we calculate the percentage change as thus:
%Change = (Final - Initial)/Initial * 100%
Where the initial number of trees =5400 and final = 1868
%Change = (1868 - 5400)/5400 * 100%
%Change = -3532/5400 * 100%
%Change = -3532%/54
%Change = -65.4%
The negative sign indicates a decrements or reduction.
Hence, percentage decrement = 65.4% and this is over 65%
