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Number Systems -Sequence and Series

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Number Systems -Sequence and Series

by sukhman » Thu Oct 17, 2013 7:09 am
S is the infinite sequence S1 = 2, S2 = 22, S3 = 222,...Sk = Sk-1 + 2(10k-1). If p is the sum of the first 30 terms of S, what is the eleventh digit of p, counting right to left from the units digit?
1 2 4 6 9

How do we solve this type of progression which seems to be of both types arithmetic and geometric
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by GMATGuruNY » Thu Oct 17, 2013 7:17 am
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