Find the 20th and nthterms of the G.P. 5/2, 5/4, 5/8, ………

Asked by Abhisek | 1 year ago |  79

##### Solution :-

Given G.P. is $$\dfrac{5}{2}$$, $$\dfrac{5}{4}$$, $$\dfrac{5}{8}$$, ………

Here, a = First term = $$\dfrac{1}{2}$$

r = Common ratio = (5/4)/(5/2) = $$\dfrac{1}{2}$$

Thus, the 20th term and nth term

$$a_{20}=ar^{20-1} =\dfrac{5}{2}(\dfrac{1}{2})^{19}$$

$$\dfrac{5}{(2)^{20}}$$

$$a_n=ar^{n-1} =\dfrac{5}{2}(\dfrac{1}{2})^{n-1}$$

$$\dfrac{5}{(2)^n}$$

Answered by Pragya Singh | 1 year ago

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