consider the sequence 1,-2,3,-4,5,-6...... what is the average of the first 200 terms of sequence?
a. -0.5
b. -1
c. 0
d. 0.5

• a )ans -0.5
• 9 years agoHelpfull: Yes(13) No(0)
• (1-2=-1)+ (3-4=-1)+...............(199-200=-1)=100(-1)/200=-0.5
• 9 years agoHelpfull: Yes(13) No(2)
• 1,-2,3,-4,5,-6.....-200
  (1+3+5+7...199)+(-2-4-6.....-200)
  this is both AP so average of AP
  (a+b)/2
  ( 1+199)/2+(-2-200)/2=100+(-101)=-1
  so ans is (b)
• 9 years agoHelpfull: Yes(4) No(7)
• (1+-2)=-1
  (3+-4)=-1
  similarly 100 terms so the sum is -100
  avarage=-100/200
  -.5
  ans a
• 9 years agoHelpfull: Yes(3) No(0)
• 1-2= -1+ 3-4= -1 + .............+ 199-200= 200(-1)/200=-1
• 9 years agoHelpfull: Yes(1) No(6)
• ans-a. - 0.5
• 9 years agoHelpfull: Yes(1) No(0)
• s/t=a
  -100/200=-0.5
• 9 years agoHelpfull: Yes(1) No(0)
• Every time two terms are going to subtract then -1 are 100 in number
  Then sum of such 100 numbers and whole divided by 200 biz we r dividing 200 before
  Simplification . So ( -1-1-1-1.....-1 which are sum of- 100)% total
  Numbers is 200 and is 0.5
• 9 years agoHelpfull: Yes(0) No(1)
• it consists of two series...
  1,3,5,......and -2,-4,-6,......
  first find the sums of the series and find the avg ans is -0.5
• 9 years agoHelpfull: Yes(0) No(0)
• -100/200 = -0.5
• 9 years agoHelpfull: Yes(0) No(0)
• use s=n(a+l)/2={50*(1+199)-50*(2+200)}/200
• 9 years agoHelpfull: Yes(0) No(0)
• Ans: -0.5
  Sum of 100 odd terms = 10000
  Sum of 100 even -ve terms=-10100
  Average=(-10100+10000)/200=-0.5
  
• 9 years agoHelpfull: Yes(0) No(0)
• these are Consecutive number the difference between the number is = -1
  the average of 200 terms is = -1/2=-0.5
• 9 years agoHelpfull: Yes(0) No(0)
• In consicutive 2 munber sum is -1.So in first 200 term sum will be -100.So the average is -0.5.
• 9 years agoHelpfull: Yes(0) No(0)
• -0.5
• 9 years agoHelpfull: Yes(0) No(0)