Question

What is the 83rd term of the arithmetic sequence {a_n} = {-22, -18, -14,...}

a. -350
b. 302
c. 306
d. 354

Answer 1

The answer is c. 306

Arithmetic sequence is: x(n) = a1 + d(n - 1)
x(83) = ?

{a_n} = {-22, -18, -14,...}
a1 = -22
d = a2 - a1 = -18 - (-22) = - 18 + 22 = 4


x(n) = a1 + d(n - 1)
x(83) = -22 + 4 * (83 - 1)
x(83) = -22 + 4 * 82
x(83) = -22 + 328
x(83) = 306