Question

Which term of G. P : 3, 9, 27, .......... is 2187

Answer 1

a = a₁ = 3 ; a₂ = 9
Common ratio,r = a₂/a₁ = 9/3 = 3
nth term of GP : an = arⁿ⁻¹
2187 = 3(3)ⁿ⁻¹
2187 = 3¹⁺ⁿ⁻¹
3⁷ = 3ⁿ
n = 7

Therefore, 7th term of given GP is 2187

Hope it helps

Answer 2

Hi friend,

Given,
a = a₁ = 3 ; a₂ = 9

Common ratio,

r = a₂/a₁ = 9/3 = 3

nth term of GP : an = arⁿ⁻¹

2187 = 3(3)ⁿ⁻¹

2187 = 3¹⁺ⁿ⁻¹

3⁷ = 3ⁿ
n = 7


Therefore, 7th term of given GP is 2187.

Hope this helped you a little!!!