Respuesta :

Answer:

The number of terms of the G.P. is 6

Step-by-step explanation:

Let the G.P. has first term a, common ratio r and the number of terms n.

The G.P. has first term 2, so a = 2.

Now, the fourth term is 54 i.e. ar³ = 54

⇒ 2r³ = 54

⇒ r³ = 27

r = 3

Now, the last term i.e. the nth term is= [tex]ar^{n - 1} = 486[/tex]

⇒ [tex]2 \times 3^{n - 1} = 486[/tex]

⇒ [tex]3^{n - 1} = 243 = 3^{5}[/tex]

Hence, (n - 1) = 5

⇒ n = 6

So the number of terms of the G.P. is 6 (Answer)

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