Equation of y, the population size after x hours is y = 1000 (1.15)ˣ
<h3>Further explanation</h3>
Firstly , let us learn about types of sequence in mathematics.
Arithmetic Progression is a sequence of numbers in which each of adjacent numbers have a constant difference.


<em>Tn = n-th term of the sequence</em>
<em>Sn = sum of the first n numbers of the sequence</em>
<em>a = the initial term of the sequence</em>
<em>d = common difference between adjacent numbers</em>
<em />
Geometric Progression is a sequence of numbers in which each of adjacent numbers have a constant ration.


<em>Tn = n-th term of the sequence</em>
<em>Sn = sum of the first n numbers of the sequence</em>
<em>a = the initial term of the sequence</em>
<em>r = common ratio between adjacent numbers</em>
Let us now tackle the problem!
Let :
Initial number of population = a
After 5 hours → Population = y = a × 2 = 2000
2a = 2000
a = 2000 ÷ 2
a = 1000
After 10 hours → Population = y = a × 2 × 2 = a × 2² = 1000 × 2²
After 15 hours → Population = y = a × 2 × 2 × 2 = a × 2³ = 1000 × 2³
After x hours ↓
Population = y = 
Population = y = 
Population = y = 
Let's prove the equation above :
After 5 hours :
Population = y =
= 2011 ≈ 2000 ✔
After 10 hours :
Population = y =
= 4046 ≈ 4000 ✔
After 15 hours :
Population = y =
= 8137 ≈ 8000 ✔
<h3>Learn more</h3>
<h3>Answer details</h3>
Grade: Middle School
Subject: Mathematics
Chapter: Arithmetic and Geometric Series
Keywords: Arithmetic , Geometric , Series , Sequence , Difference , Term