182
91
63
28
Correct answer is B
Tn=arn−1 (nth term of a G.P)
T4=ar3=189
7×r3=189⟹r3=27
r=3√27=3
Sn=a(rn−1)r−1
S3=7(33−1)3−1
= 7×262=91
If x + y = 12 and 3x - y = 20, find the value of 2x - y ...
If O is the centre of the circle, < POS equls ...
If cotθ = 815, where θ is acute, find sinθ...
If 3xo 4(mod 5), find the least value of x...
If w varies inversely as uvu+v and w = 8 when u = 2 and v = 6, find a re...
Given that p = 2, q = -5 and r = - 4, evaluate 3p2 - q2 - r3...