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| Question 1140702:  t is an even number in the series 1/t + 3/t + 5/t +.......+ t-1/t
 (1) Determine the number of terms in the series in terms of t.
 (Determine the sum of the series in terms of t.
 (3) Hence or otherwise evaluate :
 (1/4 + 3/4) + (1/6 + 3/6 + 5/6) + (1/8 + 3/8 + 5/8 +7/8)+.....+ (1/50 + 3/50 + 5/50)+....+(49/50)
 Can I get help please
 Answer by greenestamps(13209)
      (Show Source): 
You can put this solution on YOUR website! 
 The series is arithmetic, with a common difference of 2/t.
 
 (1) To find the number of terms in an arithmetic series...
 find the difference between the last and first terms;
 divide by the common difference; and
 add 1.
 
 
  
  
  
  
 ANSWER (1): The number of terms in the series is t/2.
 
 (2) The sum of the terms of any series is the number of terms, multiplied by the average of all the terms; since this sequence is arithmetic, that means the sum is the number of terms, multiplied by the average of the first and last terms.
 
 
  
  
  
 ANSWER: (2): The sum of the terms in the series is t/4.
 
 (3) The terms in this series are all of the form in the above discussion.  The values of t in the terms of this series are 4, 6, 8, ..., and 50.  So the sum of this series, using the result in (2), is
 
 
  ... +  
 This is again an arithmetic series; the sum is number of terms, multiplied by the average of the first and last:
 
 
  
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