Question

for the geometric sequence with a1=4 and r=5, find a5

Answer 1

General form of a geometric sequence:

A(n) = A1 × r^(n-1)

A(5) = 4 × 5^(5-1)

A(5) = 4 × 5^(4)

A(5) = 4 × 625

A(5) = 2500