Answer: C. 2n+1
Explanation:
The sequence of numbers is
3,5,7,9
The terms are increasing at a linear rate. This means that it is an arithmetic progression. The difference between two successive terms is constant. This is the common difference. The formula for the nth term of an arithmetic sequence is expressed as
Tn = a + (n - 1)d
Where
Tn is the nth term of the arithmetic sequence.
d is the common difference of the arithmetic sequence.
n is the number of terms in the arithmetic sequence.
From the information given
a = 3
d = 5 - 3 = 7 - 5 = 9 - 7 = 2
Tn = 3 + 2(n - 1)
Tn = 3 + 2n - 2
Tn = 3 - 2 + 2n
Tn = 2n + 1