consider sequence 1 ,-2, 3, -4,5,-6....., what is average of first 200 numbers

• Two series:
  1st series: 1,3,5,7......199 Sum = [n(a+l)]/2 = 10000
  2nd series: -2,-4,-6....-200 Sum = [n(a+l)]/2 = -10100
  Average = [10000-10100]/200 = -[1/2] = -0.5
• 9 years agoHelpfull: Yes(14) No(1)
• (1-2)+(3-4)+(5-6)+......(199-200) = -1(100)
  average = -100/200 = -0,5
• 9 years agoHelpfull: Yes(5) No(0)
• sum of 1st two number 1-2=-1
  3&4th number 3-4=-4
  there will ne 100 pairs like this
  total sum =-100
  average -0.5
• 9 years agoHelpfull: Yes(2) No(0)
• we can write as follows..
  (1 , 3 , 5 , 7.............199) + (-2 , -4 , -6 , - 8 ......... -200)
  (1+199)/2 +(-2 -200)/2
  200/2 +-202/2
  (100-101)/2
  =0.5
• 9 years agoHelpfull: Yes(2) No(0)
• -0.5 because is there are 100 p+ve and 100 n-ve no's so average of these are -100/200
• 9 years agoHelpfull: Yes(0) No(0)
• 18. On the calenders page shown a 3*3 block of numbers has a sum of 198. What is the smallest number in the block in april month
  sunday
  mon
  Tuesday
  Wednesday
  Thursday
  friday
  Saturday
  
  
  1
  2
  3
  4
  5
  
  
  
  30
  
  
  
  a)14 b)10 c)9 d)13
  19.we know that the vertices of quadrilateral A,B,C,D are 2,5,6,3 cms respectively from a point p what is the largest possible area in sq.cms of ABCD a)16 b)48 c)32 d)24
  20. Rs.7791 is divided among shills=a ,beena and chris in such a way that if Rs.34 Rs.32 and Rs.29 be deduced from their respective shares they are left with money in the ratio 8:6:12 find shilas share in rupees a)2402 b)1798 c)1808 d)2397
• 9 years agoHelpfull: Yes(0) No(0)
• Given sequence containing odd numbers and -ve even numbers,
  so that ,sum of even numbers =200/2(2*(-2)+(200-1)*-2)
  =-40200
  sum of odd numbers=200/2(2*(1)+(200-1)*2)
  =40000
  total sum=40000-40200
  =-200
  Average=total/200
  =-200/200
  =-1.
• 9 years agoHelpfull: Yes(0) No(1)
• Ans = -0.5
  bcz (100-101)/2
• 9 years agoHelpfull: Yes(0) No(0)