Find the 7th and nth terms of the GP 0.4, 0.8, 1.6….

Given GP is 0.4, 0.8, 1.6….


The given GP is of the form, a, ar, ar2, ar3….


Where r is the common ratio.


First term in the given GP, a1 = a = 0.4


Second term in GP, a2 = 0.8


Now, the common ratio,



Now, nth term of GP is, an = arn – 1


So, the 7th term in the GP,


a7 = ar6


= 0.4 x 26


= 25.6


nth term in the GP,


an = arn – 1


= (0.4)(2) n – 1


= (0.2)2n


Hence, 7th term = 25.6 and nth term = (0.2)2n


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