SOLUTION: Solve for x if 199 + 195 + 191 + ... + 7 + 3 = x + 1 + 5 + ... 189 + 193 + 197.

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Question 1142922: Solve for x if 199 + 195 + 191 + ... + 7 + 3 = x + 1 + 5 + ... 189 + 193 + 197.
Answer by ikleyn(52818) About Me  (Show Source):
You can put this solution on YOUR website!
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If


    199 + 195 + 191 + ... + 7 + 3 = x + 1 + 5 + ... 189 + 193 + 197


then (re-group)


    (199-197) + (195-193) + (191-189) + . . . + (7-5) + (3-1) = x,  or


        2     +     2     +     2     + . . . + 2 + 2 = x   


(addend "2" repeats  %28199-3%29%2F4%2B1 = 49 + 1 = 50 times).


So,  x = 2*50 = 100.      ANSWER