1 + 4/7 + 9/49 + 16/343 + .......... to infinity
x = 1 + 4/7 + 9/49 + 16/343 + ...multiply by 7:7x = 7 + 4 + 9/7 + 16/49 + 25/343 + ...subtract:6x = 10 + 5/7 + 7/49 + 9/343 + ...multiply by 7:42x = 70 + 5 + 7/7 + 9/49 + 11/343 + ...subtract:36x = 65 + 2/7 + 2/49 + 2/343 + ...multiply by 7:252x = 525 + 2 + 2/7 + 2/49 + 2/343 + ...subtract:216x = 462
divide:x = 462/216 = 77/36
blackjack
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flooble's webmaster puzzle
solution
