consider the sequence 1,-2,3,-4,5,-6......what is the Average of the first 200 terms of the sequence?

• (1-2)=-1
  (3-4)=-1.....similarly (199-200)=-1
  so total 100 set.
  (-1)100/200 =-0.5
  ans=-0.5
  
• 9 years agoHelpfull: Yes(5) No(0)
• 1+3+5.....n=n^2 {here n=100} , -(2+4+6.....)=-[n(n+1)] {here n=100 }
  total sum=n^2-n(n+1)=-n
  average= sum/no.of terms
  = -n/200
  =-100/200
  =-0.5
• 9 years agoHelpfull: Yes(2) No(0)
• 7
  odd positions--> 1 3 5 and hence 7
• 9 years agoHelpfull: Yes(0) No(0)
• no. of terms =200 means 100 odd and 100 negative even
  
  sum of 1+3+5.........n = n^2 and sum of -(2+4+6......n) = -[n(n+1)]
  
  total sum = n^2-n(n+1) = 100^2-[100(100+1)] = 10000-10100 = -100
  
  average=Total sum/no. of total terms
  
  = -100 / 200
  
  =-0.5
• 9 years agoHelpfull: Yes(0) No(0)
• -100/200=-.5
• 9 years agoHelpfull: Yes(0) No(0)
• -100/200=-.5
  
• 9 years agoHelpfull: Yes(0) No(0)