Sequence Marathon

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Sequence Marathon

by dtweah » Thu May 28, 2009 5:58 am
If S1 = 9, S2 = 99, S3 = 999, S4 = 9999, ...... what is S20-S19?

A.( 3^2)(10^19)
B.( 3)(10^20)
C. (3)^3 (10^19)
D. (3) ( 10^19)
E. ( 3)^3 ( 10^18)
Source: — Problem Solving |

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by abhinav85 » Thu May 28, 2009 6:02 am
IMO A