Answers

2015-04-12T15:25:25+05:30
Call the required sum  S.

The first sum deposited at the end of first year gets compounded two times, the second sum at the end of second year gets compounded one time and the last sum accumulates no interest.  

 S(1+0.05)^2 + S(1+0.05) + S = 50440

You can solve S.
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