Please explain how you got the question because i have no idea how to plug in the numbers

Given sequence:
[tex]\frac{1}{2},\text{ }1,\text{ }\frac{3}{2},2[/tex]To find the 109th term, we need to first determine whether the sequence follows an arithmetic progression or a geometric progression.
Check
The sequence is arithmetic if the successive terms of the sequence are formed by adding or subtracting a value.
The sequence is geometric if the successive terms of the sequence are formed by multiplying or dividing by a value.
We have that:
first term = 1/2
second term = 1
third term = 3/2
Taking the difference of the second term from the first term:
[tex]\begin{gathered} =\text{ 1-}\frac{1}{2} \\ \text{ = }\frac{1}{2} \end{gathered}[/tex]Taking the difference of the third term from the second term:
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