Question

Find the 10th term of the geometric sequence whose common ratio is 1/3 and whose first term is 7
.

Answer 1

The nth term is a_n = a_1 r^(n-1). So

a_10 = 7*(1/3)^(9) = 7 / 3^9 = 7/19683 ≈ 0.00035546.