What is the sum of all the numbers from -203 to 200?
a.-606
b.606.
c.3
d.-3
e.404
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smar83
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Is the answer A?
If yes, then sum = average * # ( no. of terms) ----- (1)
Average = ( -203+200)/2 = -3/2
I am assuming that we are counting these #'s as inclusive, then:
no. of terms = ( Last - first) +1
= (200 -(-203))+1 = 404
substitute the above in (1) you get -606.
If yes, then sum = average * # ( no. of terms) ----- (1)
Average = ( -203+200)/2 = -3/2
I am assuming that we are counting these #'s as inclusive, then:
no. of terms = ( Last - first) +1
= (200 -(-203))+1 = 404
substitute the above in (1) you get -606.
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rkanthilal
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IMO A -606.
I had a different solution. The numbers from 1 to 200 and -1 to -200 cancel out when added together. So you are left with the sum of -201, -202, and -203. The sum of these numbers is -606.
I had a different solution. The numbers from 1 to 200 and -1 to -200 cancel out when added together. So you are left with the sum of -201, -202, and -203. The sum of these numbers is -606.
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rkanthilal
- Master | Next Rank: 500 Posts
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- Joined: Thu Aug 26, 2010 9:32 am
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Hi smar83,smar83 wrote:@rkanthilal..
do you mean different approach? we both got the same answer.
Sorry. I meant a "different approach".
