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consider the sequence 1,-2, 3, -4, 5 what is the average of first 200 terms
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- 1-2=-1,3-4=-1,5-6=-1......then avg -(100)/200=-1/2
- 8 years agoHelpfull: Yes(26) No(0)
- If we calculate the average of the first two terms of the given sequence then we get,
{1+(-2)}/2 = -0.5
Similarly, average of the first 4 terms = (1-2+3-4)/4 = -0.5
Similarly, average of the first 6 terms = -0.5
Hence, for every even number of terms considered, the average will remain constant i.e., -0.5
So average of first 200 terms will also be -0.5; since 200 is even. - 8 years agoHelpfull: Yes(13) No(0)
- sum of 1st 2 terms = -1
sum of 1st 4 terms = -2
sum of 1st 6 terms = -3 and so on...
hence sum of 1st 200 terms = -100 - 7 years agoHelpfull: Yes(4) No(0)
- n/2(a+l)
100/2(1+199)=50*200=10000
100/2(-2+-200)=50*-202=-10100
so 10000-10100/200=-1/2 - 8 years agoHelpfull: Yes(2) No(1)
- since 1+(-2)= -1
3+(-4) = -1
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99+(-100)=-1 uptil 100 the sum=-50
similarly for another 100 digits uptil 200 sum=-50
total sum uptil 200 = -50 +(-50)= -100
therefore, average= -100/200= -1/2 - 7 years agoHelpfull: Yes(2) No(0)
- Average=(1-2+3-4+5-6+7-8.......)/200
= (-1-1-1-1......)/200
=-100/200
=-0.5 - 7 years agoHelpfull: Yes(1) No(1)
- a+(n-1)d=1+(200-1)(-1)=-98
- 7 years agoHelpfull: Yes(0) No(1)
- Series is divided into two terms 1,3,5.... will contain 100 terms
and second series is -2 ,-4,-6
S=n/2*(2a+(n-1)d)
so first series give s=10000
second series give s=-10100
add the two series and divide it by 200
so avg=-100/200
ie ans=-0.5 - 7 years agoHelpfull: Yes(0) No(0)
- Average=(1-2+3-4+5-6+7-8...........)/200
(-1-1-1-1-1-1-1......)/200
-100/200=-0.5 - 7 years agoHelpfull: Yes(0) No(1)
- Answer will be -50
Explanation
-----------------
we have
1 ,-2, 3, -4, 5 ........
rearrange and take sum,
(1+3+5+7+....+199) - (2+4+6+8+....+200) ;both AP series has exactly 100 terms
=100/2(1+199)-100/2(2+200)
=50*200 - 50*202
= -50*2
average =-50*2/2
= -50 - 7 years agoHelpfull: Yes(0) No(3)
- all even terms in the series are negative and all odd terms are positive ....200th term will be even...so the sum of 200 terms will be...(1+3+5+...+199) - (2+4+6+...+200)=-100
- 7 years agoHelpfull: Yes(0) No(0)
- for each two terms the difference will be -1 so for 200 terms it will be -100
AVERAGE = - 100 / 200 = - 0.5 - 7 years agoHelpfull: Yes(0) No(0)
- avg of first two numbers is -1/2;
avg of first three numbers is 2/3;
then the avg of first 200 terms is -1/2 - 7 years agoHelpfull: Yes(0) No(0)
- L takes place after R
- 7 years agoHelpfull: Yes(0) No(1)
- -100
1-2=-1
3-4=-1.....100 times - 7 years agoHelpfull: Yes(0) No(0)
- -0.5
1-2=-1
3-4=-1....100 times
-100/200=-0.5 - 7 years agoHelpfull: Yes(0) No(0)
- 1-2+3-4+5=3 this is for first 5 numbers.let us consider it for all 200 terms as 200/5=40
then 40*3=120 - 6 years agoHelpfull: Yes(0) No(1)
- (-100+101)/200=1/200
- 4 years agoHelpfull: Yes(0) No(1)
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