[tex]T_n = a_1 + d(n - 1)[/tex]
When a = 18, d = 4, find the nth sequence:
[tex]T_n = 18 + 4(n - 1)[/tex]
[tex]T_n = 18 + 4n - 4[/tex]
[tex]T_n = 14 + 4n[/tex]
When the nth term is 4018, find the value of n:
[tex]14 + 4n = 4018[/tex]
[tex]4n = 4018 - 14[/tex]
[tex]4n = 4004[/tex]
[tex]n = 1001[/tex]
Answer: 1001 term must be added to obtain the sum of 4018.
