The 6 term of a G.P is -2\27 and it's first term is 18.what is the common ratio

Question

asked Jan 25, 2021 93.7k views

1 Answer

Deepak Bala · Answer 1 · 2021-01-28T19:18:49+0000

Answer:

r = -
(1)/(3)

Explanation:

The n th term of a GP is

a_(n) = a₁
r^(n-1)

where a₁ is the first term and r the common ratio

Here a₁ = 18 and a₆ = -
(2)/(27) , then

18
r^(5) = -
(2)/(27) ( divide both sides by 18 )

r^(5) = -
(1)/(243) ( take the fifth root of both sides )

r =
$\sqrt[5]{-(1)/(243) }$ = -
(1)/(3)