Q28 Talent Test

+1 vote

1+2(1/2) + 3(1/4) + 4(1/8)+….. =

asked Apr 8, 2017 in Aptitude by getgatebook (33,570 points)
reshown Apr 9, 2017 by getgatebook

2 Answers

0 votes
Answer will be 4
answered Apr 9, 2017 by chandrasish96 (360 points)
+2 votes
Let, I=1+2(1/2) + 3(1/4) + 4(1/8)+...  eqn 1

    1/2*I=   1*(1/2)+2(1/4)+3(1/8)+..     eqn 2

so subtracting 2 from 1

1/2 *I=1+1/2+1/4+---

so,I=2*(1/(1-1/2)) = 4
answered Apr 11, 2017 by (230 points)
Answer:
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