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Simplification
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vipinsharma
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Please answer this.I am unable to solve this.The sum of the first 40 terms of the series:1/2+1/3-1/4-1/2-1/3+1/4+1/2+1/3-1/4
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Hi vipinsharma,
This question is either badly worded or incomplete...
We're asked for the sum of the first 40 terms...
I believe that the "intent" of this prompt is that the sequence (of 6 terms) is repeating....
1/2 + 1/3 -1/4
-1/2 -1/3 + 1/4
....
1/2 + 1/3 - 1/4
-1/2 - 1/3 + 1/4
etc.
If that IS the case, then every set of 6 terms "offsets" and sums to 0.
This means that we can ignore the first 36 terms (since that would be 6 full sets of 6 terms; that sum would be 0). We'll focus on the final 4 terms of the first 40 terms...
1/2 + 1/3 - 1/4 - 1/2....
The 1/2 and -1/2 offset, so we're left with...
1/3 - 1/4
For this we need a common denominator...
4/12 - 3/12 = 1/12
GMAT assassins aren't born, they're made,
Rich
This question is either badly worded or incomplete...
We're asked for the sum of the first 40 terms...
I believe that the "intent" of this prompt is that the sequence (of 6 terms) is repeating....
1/2 + 1/3 -1/4
-1/2 -1/3 + 1/4
....
1/2 + 1/3 - 1/4
-1/2 - 1/3 + 1/4
etc.
If that IS the case, then every set of 6 terms "offsets" and sums to 0.
This means that we can ignore the first 36 terms (since that would be 6 full sets of 6 terms; that sum would be 0). We'll focus on the final 4 terms of the first 40 terms...
1/2 + 1/3 - 1/4 - 1/2....
The 1/2 and -1/2 offset, so we're left with...
1/3 - 1/4
For this we need a common denominator...
4/12 - 3/12 = 1/12
GMAT assassins aren't born, they're made,
Rich
