Arithmetic Sequence Terms
Suppose an arithmetic sequence is defined by this explicit formula.
an = 20 + (n − 1)4
Question 1
Determine a25.
Responses
A45
45
B116
116
C130
130
D162
To determine a25, we substitute n = 25 into the formula.
a25 = 20 + (25 - 1)4
a25 = 20 + 24*4
a25 = 20 + 96
a25 = 116
Therefore, the correct answer is B) 116.