Find the 4th term from the end of the G.P. 2/27, 2/9, 2/3, …., 162.

Question

Find the \( 4^{th}\) term from the end of the G.P. \( \dfrac{2}{27}, \dfrac{2}{9}, \dfrac{2}{3}, …., 162.\)

Asked by Sakshi | 1 year ago | 83

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Accepted Answer

The nth term from the end is given by:

Given: last term, l = 162

r= \(\dfrac{ 2}{9} × \dfrac{27}{2}\)

= 3

n = 4

So, a_n = l (\( \dfrac{1}{r}\))^n-1

a₄ = 162 (\( \dfrac{1}{3}\))^4-1

= 162 (\( \dfrac{1}{3}\))³

= 162 × \( \dfrac{1}{27}\)

= 6

4^th term from last is 6.

Answered by Sakshi | 1 year ago