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Sequence

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Sequence

by dtweah » Thu May 28, 2009 5:09 am
If in a sequence T1 = 2, T2 = 5, T3 = 11, T4 = 23, T5 = 47, What is T7?

A. 95

B. 96

C. 173

D. 181

E. 191
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by sacx » Thu May 28, 2009 5:24 am
T2-T1 = 3
T3-T2 = 6
T4-T3 = 12
T5-T4 = 24
T6 - T5 = 48, T6 = 95
T7-T6 = 96, T7 = 191
SACX
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by abhinav85 » Thu May 28, 2009 5:48 am
IMO E
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by scoobydooby » Thu May 28, 2009 10:34 am
by observation each term is 2 times the previous+1

T6: 2*47+1=95
T7: 2*95+1=191

hence, E
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by ghacker » Wed Jun 10, 2009 10:14 am
The answer is =4*47+3 = 191


or 47+144 = 191 ( the pattern is 3,6,12,24 so no )
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by ketkoag » Thu Jun 11, 2009 4:56 am
pattern is Tn = 2*T(n-1) + 1
hence E would be the answer.
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