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If 64,27,36 are the Pth,Qth and Rth terms of a G.P., then P+2Q is equal to (a) R (b) 2R (c) 3R (d) 4R

Asked by aliencpr31 | 31 Jul, 2019, 10:55: AM

Expert Answer

We know that,

n^th term of a G.P is given by,

t_n = ar^n-1

According to the question,

a. r^P-1 = 64 ... (1)

a. r^Q-1 = 27 ... (2)

a. r^R-1 = 36 ... (3)

To find: P + 2Q = ?

Hint :

P is having a coefficient 1 , Q is having a coefficient 2 and from the options

if we take 3R , so the cofficient of R is 3.

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Answered by Yasmeen Khan | 31 Jul, 2019, 14:28: PM

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