The greatest positive integer k , for which 49 k + 1 is a factor of the sum 49 125 + 49 124 + … + 49 2…

The greatest positive integer k, for which 49k+1 is a factor of the sum 49125+49124+…+492+49+1, is
  1. 32
  2. 63
  3. 60
  4. 35

Solution

This series is a G.P. with first term 49125 and common ratio 149.

So, its sum =49126-148=4963+14963-148

Asked in: JEE Main 2020 (07 Jan Shift 1)

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