4. 1-2+3-4+5-6….. what is the average of first 200 terms of this sequence?

• -(1+1+1.....upto 100 trms)/200
  =-1/2
• 11 years agoHelpfull: Yes(47) No(0)
• Taking one ODD term and one EVEN term in pair, we get 100 such pairs.
  (1-2)+ (3-4)+ (5-6)+...
  this gives (-1) added 100 times.
  So the sum is (-100).
  For the average, divide the sum by 200.
  Hence, Answer wil be = (-100)/200 => (-1/2)
• 11 years agoHelpfull: Yes(22) No(0)
• 1+3+5....199=10000
  -2-4-6-8....-200=-10100
  add both of them
  -100
  now avg=-100/200= -1/2 will be ans
• 11 years agoHelpfull: Yes(6) No(0)
• 1-2=-1
  2-3=-1
  .
  .
  ..
  200 terms then -1-1-1........till 200th term = -200
  and avg=-200/200
  = -1
  ans is -1
  
• 11 years agoHelpfull: Yes(5) No(28)